I thought most people who own monero also self custody. Wouldn't that make exchanges have a hard time suppressing the price? The lower the price, the less fiat is needed to accumulate xmr and move them to cold storage.  

 Binance and OKX just have delisted after having Monero withdrawals closed for months/years.

There are still a few other (weaker) CEX trying to control the price through various mechanisms. 

 Binance still allows withdrawals.

https://www.binance.com/en/support/announcement/binance-will-delist-ant-multi-vai-xmr-on-2024-02-20-f73b083ba6834771b07dbe5319917ae5