Should I stack Ethereum?
Yes, but not there because "not your keys, not your coins".
Honestly, if a person needs to ask this sort of question, we can consider them as new in the crypto world and they might be better off by sticking with places like coinbase until they are tech-savvy enough to secure their cryptos. Because reputable places like Coinbase has way better security measures then any newb could provide for themselves.
Now i know this is against the decentralized ideology, but if we want adoption, we must be aware that there will be people joining that need custody solutions from third parties.
It's good that as soon as they've entered the market, they're already aware that if they don't hold the keys, it's not their coins. Because many are still not aware of that thing despite staying in the market, they're relying on the exchanges as wallets.
And that's not a good thing if that's how they treat the exchanges. Whether they're new or not, as long as they're introduced already how exchanges and wallet works, they should know the thing about owning the keys.