If you wish to hold some coin then use exchange only for during exchange. Just exchange your coin and transfer on your personal wallet that you have controlled. Specially you can use hardware wallet.
Because many exchange hacked buy hacker. Many people loss their capital by hack.
So please don't hold your coin on exchange for long time.
You have a point because there are market's that cannot actually handle the growth of cryptocurrency and sometimes there are hacking issues as well due to their weak security so i prefer using ledger than.