It's still a mistery if once the hype ends the games will remain functional. I think a good example to be watched is Axie Infinity which seems to have lost its momentum, as there isn't a constant flux of new players anymore to keep the prices of the axies and SLP expensive.

The problem with these games is sustainability. The infinite supply of raw materials created in game are too much at some point to maintain the perfect balance between demand and supply. Furthermore, players who cheat the games through methods to automatize the gameplay (bots) are a big issue at online games in general, which totally crash games' economies, devaluing goods' values and creating excessive supply.

If play to earn games' developers where able to ban bots, the economy would become more competitive, healthy and encouraging to legit players to invest their time and money on this activity. Sadly it doesn't happen, consequently making some players suspect the platforms' managers benefit themselves somehow by the chaos promoted by the cheaters...