I know we could go on forever but wow the Charge Beam one in particular really is bizarre.I also think that alongside the most-definitely balance-minded Toxic/Knock Off/Scald curbing, the dropping of very specific Pokemon from other old TM compatibility feels random (see for instance: why did only Blastoise and Tentacruel lose Waterfall? Jolteon and Zapdos losing Charge Beam?) but that could go on forever. The one exception to me besides the aforementioned big three is Dual Wingbeat Dragonite, which I suspect was based on the popularity of Tera Normal Extreme Speed sets, but the rest of the losses I can find aren't even close to competitively viable.
Like Jolteon & Zapdos I...guess, if I squint, I can see it. Like oh, we don't want the fast & strong electric type to get it anymore. we don't want the other strong electric type to get it either. Same with Mewtwo, maybe?
Weird, not like anyone was really using the move, but. Sure. I guess. I can see the shape of a decision
but Wigglytuff? Chansey? The Drifblim line??? Meloetta & Hoopa had better things to do and are banned anyway, why bother....
Dunsparce lost it and its like, you already let it keep Calm Mind, I think any special attacking Dudunsparce spamming Boomburst & hurricane are just going to use that.