That's a very good trap and the best part is that if White doesn't fall for the trick (e.g. 2. Nf3) Black still has a very good game.
If you are wondering: What happens if they take with the pawn? It's the same story, the bishop is trapped after: 1. d4 d5 2. Bf4 h5 3. e3 e5 4. dxe5 g5
This is not a very well known trap and if we go into lichess base we can see that 1/3 of the players will play e3.
Wow, that's actually quite an ingenious trap! Great job!
That is a fun trap, indeed.
Though I'm going to spoil black's fun here and give London players an easy out.
Now, dear London player, you may continue with your regularly scheduled programming. 
That's a very good trap and the best part is that if White doesn't fall for the trick (e.g. 2. Nf3) Black still has a very good game.
If you are wondering: What happens if they take with the pawn? It's the same story, the bishop is trapped after: 1. d4 d5 2. Bf4 h5 3. e3 e5 4. dxe5 g5
This is not a very well known trap and if we go into lichess base we can see that 1/3 of the players will play e3.
I wouldn't exactly say Black has a "very good game". h5 is a pretty weakening move of the g5 square and of course does not contribute to the fight for the center. White is definitely for choice after 3.Nf3.
If anyone tried this against me, I would just deliberately "fall for the trap", and after 1.d4 d5 2.Bf4 h5 3.e3?! e5 4.Bxe5 f6 5.Be2 fxe5 6. Bxh5+ Ke7 7.dxe5 I would prefer to have white, even though he must be considerably worse objectively. Realistically I would expect to win this position more than 50% of the time with white against someone of a similar rating.
If anyone tried this against me, I would just deliberately "fall for the trap", and after 1.d4 d5 2.Bf4 h5 3.e3?! e5 4.Bxe5 f6 5.Be2 fxe5 6. Bxh5+ Ke7 7.dxe5 I would prefer to have white, even though he must be considerably worse objectively. Realistically I would expect to win this position more than 50% of the time with white against someone of a similar rating.
Giving off grob vibes where black sacrifices the exchange because it’s good for him
I wasn't aware of that trap but If I saw 2...h5 I would immediately suspect it may be intended to trap my bishop and start looking to see if there is a problem with 3 e3. If after looking I saw a problem, or was unsure about what to think, I would use the time to play 3 h3, a move London players usually like to try to get in.
Out of curiosity (and just for the heck of it) I played 2...h5 in one of my games here when I got the opportunity. And guess what? Of course, my 2100 opponent didn't fall for the bishop trapping cheapo, but by move 16 I had positionally winning game without him making any obvious mistakes!
Here's the game: https://www.chess.com/game/live/42457825053
Yeah everyone can clearly see that it's bullet. There's wch's for classic, rapid, blitz and bullet, so I don't see your point. Besides, the op has clearly stated that he came up with the idea specifically for blitz/bullet.
Works very well in blitz and bullet when London players pre-move mindlessly.