>>43051074The problem with identified correctly (TMs were finite) but solved incorrectly (at least, if you ask me). Removing the finite nature means that there is little to stop a player from giving, say, 6 pokemon Earthquake. This causes average team strengths to skyrocket - while this does mean that you can make opponents harder too, it also means that it's hard to make opponents that are significantly stronger than the player, and it also means that level-up movepools are near-irrelevant in lategame.
The ideal solution for me would be to make TMs finite use, but add a postgame shop that lets you buy any quantity of any TM, essentially making them infinite use after the game is complete.
Alternatively, SS made a step in the right direction by making weaker TMs infinite use, but stronger TMs finite use, although I'm not keen on how many there are nor the move distributions. 
