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.
Yes, I think that at this point you should not hold and invest long term, you can see that bitcoin prices are constantly fluctuating and the market is bearish in the long run, so to be able Successful trading is very difficult, bitcoin prices can decrease at any time and if you keep the longer the damage will be larger.