So what if it's something like a 2700+ player's is when you are not playing at that level. Openings are not owned by or limited to certain rating classes. That's just elitism. You are playing it at your own level with people who are also your level.
You can get by learning the tabiya positions and then just trying it out and figuring things out as you go. This is actually a good thing as it develops your skills for finding the best moves instead of just memorising lines. If you do make a mistake then you remember it and play better next time.
The way you suggest that you have to memorise long lines of theory to play these openings in the first place is wrong. Trying and testing is a better way of learning than memorising.
It's also better to play openings which are actually fun and exciting to stay motivated and interested in the game. I would much rather play Winawer Poisoned Pawn and Fischer Sozin Attack, actually fun openings, than boring stuff like the French Exchange and Alapin Sicilian.
🙃 Fair enough. Well I think they still could have explored some fun and rich openings as well as those skills.
I don't really like the Alapin or Scandinavian. Scotch is good. You know they could play the Scotch against the Sicilian and it's more fun though lol.
I also wouldn't say it takes years of study to play an opening. What I studied of the Najdorf were basically tabia positions and some common mistakes. This didn't take that long at all. It was very casual. I still play it and have fun games and win without having memorised long lines. People exaggerate way too much when they say stuff like there's way too much theory. The people who say this are just parroting someone else's view and never tried or tested it themselves.
What takes years to build is to do "learning" for our brain's neural nets to be well trained around sets of positions. As the saying goes "it takes 2000 hours to get good at something", if the repertoire is too spread out and it's a collection of a lot of somethings like a 2700+ repertoire is, the thousands of hours required to be good at it are just too many for non-professionals.
In all thematic tabiyas the players I mentioned play best moves nearly always, in a sense their in-repertoire rating is higher than out-of-repertoire, the reason is not memorising long lines, they actually don't play openings where this is required, there's no Keres attack in their repertoires, it's because they've learnt these positions really well.
There are openings however where long forced lines need memorisation, it's a choice whether one adopts them or not though, I much prefer to live without them.
Of course one can change openings over years, even change from 1.e4 to d4 to c4, but what is not possible is play all openings at the same time. Some of these folks have gone 1.e4->1.d4->1.c4 in a course of 20 years, others prefer to play the Scotch for 20+ years, depending on how they stay motivated but what nobody did is play everything at the same point in time.