Idk what Utopiap2p is but the FTX issue simply showcased one problem, don't store your assets on exchanges. This doesn't necessarily mean you wouldn't use them anymore for their intended purpose, as an exchange, but rather use them only for that specific one and not anything more. Ofc using decentralized options would naturally be better.
With a hardware wallet, you only need to set it up and then send your funds. You can forget about it right after.
It's not the complicatedness but rather the "setting it up" process I guess? Not that I'm saying it's hard, anyone can study up on it and learn it really, but some people just choose convenience over anything else I suppose. The process in Centralized exchanges is something done in general for most account creation purposes so most people are used to it hence using it for exchanges doesn't really seem that complicated anymore.
In general, I'm just saying people are just THAT lazy, either in setting it up even if they knew how or in learning how to set it up. Especially if you consider how most people wouldn't really move till they get hit themselves.