You can still invest on DeFi project with a real business and it is still profitable. Its good that we finally goes back to a lot more cheaper fees compare before, the hype might be over but I don't think DeFi project is dead already because they made a good impact in the market with a real business. Start investing again while the market is still cheap, you just need to look for the good projects but if you are still in doubt always go to the top options and those are BTC, ETH and BNB.