FTX has taught many people an important lesson, not your keys, not your coins.
The number one thing that matters in the cryptocurrency space is self-regulation. Never put all your eggs in one basket, Take profits!
They didn't give us any lessons, FTX is not the first exchange to crash, before that many centralized exchanges have also collapsed. FTX is just reminding us again, never trust anyone in this market but yourself. Since you're new to the forum, if you've been here long enough, you'll always be reminded to never leave your money on centralized exchanges before FTX crashes.
The death of FTX reminds me that anything is possible in this market, the bigger the market, the bigger the losses, always be ready.