There were several reasons I've read about what really is happening like the miner's exit to which they are selling it for a low price so new miners will not get ROI and eventually close down. The only reason some find it sensible is that what goes up must come down, I guess this is just investors taking profit and then reinvesting again after.
I would say Defi projects was make a lot of new investors loss their money and make the market bleeding again so soon as the hype of Defi will attract a lot of scammer to make a scam project that lead to new investors losing their money and what most surprises even Binance do list scam project in their exchange.