Hi, There's no point. It's just an easy opening that's why people use this.
WHY does everyone play the London system with white

The opening is great for beginners because it's a "system" which means you can basically play it regardless of what your oponnent plays and it leads to very simple development and plans. It's boring as hell to play against but it's a great tool for the newbies.

Against the London I recommend 1.d4 nf6 2.bf4 c5. If they take then you already have good chances of dominating the center later on. If instead they play a move like 3. e3 then you can play ...qb6 and you are already causing problems that beginner players are likely to mess up against.

why does everyone play 1.d4 2.Bf4 with white ????
Everyone doesn't.
1) Is this the greatest opening in the world ?
Nope. I would say it isn't even the greatest system opening.
2) why does everyone play it but they are are not so high rated ???
They think they can play on autopilot for the first several moves and get to a playable middlegame. The problem is that people who know what they are doing won't let them do that, and even if they do get to a playable middlegame, they only learn 1 basic structure, which makes it very difficult to improve. In short, most of them will stay low rated for quite a while if they do not branch out.
3) I don't understand what is the point of this opening
White wants a Colle-type setup, but without the passive bad bishop. So, he develops the bishop outside the pawn chain and then puts all his pawns on dark squares. It is still a bad bishop, but at least it is an active bad bishop instead of a passive bad bishop.
As already stated, the appeal to many beginners is they think they can play on autopilot in the opening. If you want to see what happens when you do that, just watch this video:
#7
1 d4 Nf6 2 Nf3 and now play the regular 2...e6 / 2...g6 / 2...c5 / 2...d5 / 2...b6.
The idea of ...c5 and ...Qb6 can also be delayed.
Point is, by bringing the bad bishop Bf4 outside its pawn chain b2-c3-d4-e3-f2 it is more active, but it has left the black squares b2-c3-a3 undefended.

#7
1 d4 Nf6 2 Nf3 and now play the regular 2...e6 / 2...g6 / 2...c5 / 2...d5 / 2...b6.
The idea of ...c5 and ...Qb6 can also be delayed.
Point is, by bringing the bad bishop Bf4 outside its pawn chain b2-c3-d4-e3-f2 it is more active, but it has left the black squares b2-c3-a3 undefended.
I have 2 different things I like to play against the London, and of course they have to be flexible enough that I'm not unhappy when my opponent goes for a stonewall or colle instead... giving me 5 options on move 2 and explaining the bishop is outside the pawn chain... lol
I used to be annoyed at your advice since you're over 2000, but I've been trying some 10 minute games myself, and now I understand . My goal is to get over 2000 while playing 3 games of 10|0 at once. After my first day I got to 1930 so I think it's possible.

Well, most people who play the London setup start with 2.bf4
I don't know what they normally play. Maybe you're right, shrug*
I used to play a guy who'd do a colle or london or stonewall depending on your move order.

People play it because you don't have to use any energy or think to play it...it is uncombative and is reflective of the lazy 'I want everything for free' attitude of the internet generation.

By the way I use the London setup as black against flank openings I don't want to deal with.
For example I have theory against 1.b4, but when I'm feeling lazy and it's blitz, sometimes I just play a London setup.
A handy tip to know I guess.
#14
The London was invented as a black defence against 1 Nf3 2 c4:
https://www.chessgames.com/perl/chessgame?gid=1102115
#11
The strategem ...c5 and ...Qb6 to punish a premature sortie of Bc1 is also known from other openings
https://www.chessgames.com/perl/chessgame?gid=1993385

I could be mistaken but the London was originally played as black. I seem to recall even Emanual Lasker actually played the formation in a game as black.
At any rate, the 'London System' as white was regularly played as 2 Nf3 3 Bf4 until it eventually became understood that delaying Nf3 saved white a tempo to help deal with black's quick attack on the queenside, then 2 Bf4 caught on and breathed new life into the London.
Chess is so very theory heavy these days, that helps keep the London in the limelight. But even the London has been adding a lot of theory.
Edit: I now see tygxc had already noted it began as a black defense.

The c5 Qb6 thing looks nice but... white can easily start with 1.d4 and 2.Nf3 so...
The move order doesn't matter much when White is playing on autopilot. There are similar move order tricks Black can play with the 2. Nf3 variation as well.

I don't play it but it's a superb opening, which is suitable for all levels of play. At its easy end it's a system opening which a beginner can get the hang of easily. Yet it's suitable for all levels of play, due to its extremely complex, transpositional nature.
So there.
So its suitable for all levels of play then...

why does everyone play 1.d4 2.Bf4 with white ????
1) Is this the greatest opening in the world ?
2) why does everyone play it but they are are not so high rated ???
3) I don't understand what is the point of this opening
thanks
1) It is not. In general when you play with white, the aim is to have the initiative if you can. London System is a bit slower opening, and it is not viewed as the best try for white to achieve this. Of course, opening doesn't usually decide games, unless you are a master level player, so this is not that important for an average chess player.
2) People play it for various reasons. But, lower rated people play it because they feel they are in control. They can play similar 5-10 moves in every game and not be lost out of the opening.
3) The point is to get a playable position.
This opening realistically is not bad, so it can be played safely.
The downside for lower rated people is that they will play in a similar way 50% of their games (every game with white). This will probably become boring, and it will not give them the experience of other positions, which if you want to improve is not that great. Eventually people playing London System will probably want to play something else, and if they are playing London System for a long time, they will be worse in positions they never had on the board. The transition will be somewhat harder because they will be changing 50% of the openings they play.

Against the London I recommend 1.d4 nf6 2.bf4 c5. If they take then you already have good chances of dominating the center later on. If instead they play a move like 3. e3 then you can play ...qb6 and you are already causing problems that beginner players are likely to mess up against.
is it called the London system because some dude from London made it ?
why does everyone play 1.d4 2.Bf4 with white ????
1) Is this the greatest opening in the world ?
2) why does everyone play it but they are are not so high rated ???
3) I don't understand what is the point of this opening
thanks