Play to Earn projects are bad because they are inflationary. You imagine it like this. If their projects have good marketing, growth, more players will join, invest first and play their games. The more players play their games, the more tokens will be created in a same time. The more active players, the higher inflationary rate.
I'm not so sure about your inflationary angle since they also have burning mechanisms in place for their NFTs. The main problem with many of these P2E games is the mismanaging of their reward pool. They offered a high percentage return to players but they could not sustain it. Players leave once it is drained and move on to other games they could exploit.