My mistake. I don't like Blockchain.com/Blockchain.info because it's a web wallet, but yep you can control your funds because you have your private key etc. In my opinion, owning your own private key is still risky if you use a web wallet, you can get phished, got dns hijacked, etc. Of course it does not always happens, however the risk is too high for me.
You're absolutely right, web wallets is least safe to use, even if you have full control of your coins there. Phishing is a big probkem when we talk about web wallets and lot of people lose money because of it. If people choose to use web wallets, they shouldn't keep big amount of crypto there.
If you have very limited coin and do the daily trading or short term then can use some of the best web wallets available and store it in multiple wallets so that you can do not store everything under one wallet . Also if you do not want to use frequently then offline is the best way to safeguard it.