I'd attribute it to many factors.
- Miners were hit hard so they needed to sell their bags and find something else to mine/do.
- Some people value PoW and quit ethereum out of principle
- There are some concerns that Eth became not censorship resistance, especially after Tornado Cash
- Some people just wanted the EthPoW airdrop

This is a global market and you only saw or heard just the small fraction of it that was bullish.