I'm having a difficult time in trusting any of these online exchanges, what is to keep them from pulling out and doing an exit scam? The solution seems to be physical wallets like the Ledger or Trezor, but what is to keep the developers from putting a backdoor into the software that drains all coin once it reaches a certain amount, or to take fractions of a coin without leaving a history of such? If only have 1-2k in it thats not a gigantic hit, but lets say you have millions in coin. Is there nothing more secure one could do?
What is keeping them from doing an exit scam? perhaps going bankrupt, lose all credibility and face jail time? and this isn't even the worst case scenario the people running these exchanges could face.
But then you say that developers could put a backdoor in a physical wallet? c'mon, what's next, we can't have an encrypted air-gapped pc to store our coins because
"hey, what's stopping a burglar to just break into your house and steal all your shit?". If you are this scared then you don't have a place in the cryptocurrency market.
Seriously though, there's not much we can do other than to trust these exchanges/wallets with our coins, if you start thinking about the possibility that they're gonna steal your cryptos then you're going to start getting paranoid for no reason.