PoS inevitably leads to centralization and requires an inflationary currency supply. That is the problem. Coins in transit can't stake. Which means the only coins that can stake are coins that already exist and are sitting on a staking node. You are paying those stakers with an inflationary supply. Which means you are minting new coins and handing them to users who already have the most coins. This leads to centralization of the supply over time, and therefore, control of network consensus. A few rich, powerful people end up controlling the whole system, just like our existing banking system. No thanks.

Most of those PoS chains also have massive chain sizes/system requirements compared to Bitcoin, which means they can't be or remain nearly as decentralized, neutral, and secure.