5. You're no difference from someone using a bank because everything you do under a centralized exchange is from a central authority like the banks and other centralized institutionizations did.
Banks are better because they are likely to protect your fiat than exchanges will protect your coins. There can be robbery in your bank, you can go to another branch the next day to deposit or withdraw, you can make use of their online banking, this is the way banks operate in my country, but if an exchange is hacked, your coins are gone or inconveniences may occur.
That is good advice, banks are definitely better than centralized exchanges. There are some people who may not like banks, but they do like centralized exchanges. even though the thing that both of them did was the same, asking KYC to be able to use it. But it would be better to use a bank because Fiat funds will be safer than a centralized Exchange which does not have full control and if hacked there are no guarantees. We still depend on Fiat, but we also have to use crypto smartly.
Then regarding Op's thread, I support he investing in bitcoin, but not by saving it. Use safe storage, even all the members here advise you to store your personal bitcoin wallet because CEX is still very vulnerable.