I See you point but considerations such as,
How is an Anti-Cheat Supposed to differentiate between Fly and Someone Stuck in an invisible block?
The Answer is that Its More Complex than just Writing "Anti-Cheat Ban Fly Cheater" you probably all know that, but really no Anti-Cheat is Perfect Take Hypixels For Example People Think its the best Anti-Cheat But you see people flying, Bunny Hopping, Using Kill-Aura and etc. It's hard work for developers to keep up with these clients cause bypasses are being made. If people get false banned it'll be pretty hard to get unbanned if you don't have valid proof you weren't cheating.
It is really just Anti-Cheats Are very complex and hard to understand, as well as cheats/Hacked Clients update Very Frequently, so developers have to keep coding to keep up with new cheats. I just Recommend Recording everything you do cause that's what I do just in case I get banned, so I can justify its false.
Lastly, Anti-Cheats are not perfect, there are some problems with them, if you do get false banned, it is one the anti-cheats fault, but there is nothing we can do about it as no Anti-Cheat is Perfect. Everyone's Best Bet is To Record what they do or just Try to be as honest and detailed as possible.