How do I Properly Combat the London System

In bullet I'd actually take white anytime 

Yeah, so many people premove all the moves in the london system and usually they get away with it, because there are not a lot of tactics involved in the early stages of the opening. This opening trap isn't a good one, but it can win you a lot of games. Even if your oponnent play Nf3, the position isn't lost. Especially in fast time controls.

I learnt about that trap from Eric Rosen's video.

I highly recommend the Queens Indian defense for the London & most d4 lines, semi-slav works to. Both are solid if you put effort in, I mean this site sponsors chessable that's a great starting point for either both bave free lessons.

https://www.amazon.com/Playing-1-e4-e5-Classical-Repertoire/dp/1784830143

https://www.amazon.com/Playing-1-d4-d5-Classical-Repertoire/dp/1784830429

https://www.amazon.com/Playing-French-Grandmaster-Guide-Aagaard/dp/1907982361

But after h3 I think the positions are not as bad as after white played 3. Nf3. Most of the time white wants to retreat the bishop back to g3 in reaction to Bd6 by black. If white plays h3, Bg3 isn't available because of Bxg3 ruining the pawn structure. The more weaknesses white creates in his own camp the more black has to work with. If white plays Nf3 he was no weaknesses and black has just the worse position.

With that said, this doesn't matter much in blitz/bullet games.

Yeah, but white played h3, that's why black has it a bit easier. I never claimed that this h5 move is the greatest move. It just won me a bunch of games, because many london system players play their opening moves on autopilot.

h3 isn't the critical move. 3. Nf3 basically refutes the whole opening idea, because h5 is totally useless. After h3 black has something to work with. White unnecessarily weakened himself with h3. This weakens the kingside and can be potentially used for and kingside attack later on, which is expecially relevant in bullet of blitz. I only play this in bullet or 3 min blitz games.