This is misleading, when you're hold your coins on online service, it doesn't mean you will completely lose all of your money and can't get it back when a bad thing happen. If you're give your wealth to social institutions, war victims etc, it's donation and you don't have any access to claim back your money. The bad thing of online service is prone of hack and they will ask you many questions or KYC, but you still can access your money as long as the service isn't scam or hacked.
Not saying holding on online service is good, but your comparison aren't make sense.
Although OP might have put it out harshly but it is not far from the truth. Storing funds on them should be avoided, because if actually you lose funds due to the service or platform been hacked then the chance of getting back this funds are slim(many exchanges that have been hacked are yet to return users funds). The ones that get back their funds are mostly platforms that are closing down and they inform their users to take off their funds. But this shouldn’t be depended on because you don’t when it will be hacked.
I am probably going to stop warning people about their wallets and the dangers of reporting their Bitcoin on a exchange because they just don't care, after FTX's cruel fate I thought centralized exchanges are going to go out of business because the majority of people will stop using centralized exchanges and move out all their funds.
We can’t just stop warning people because of the newbies coming into cryptocurrency aren’t aware of its danger, it is even fact that many of them even get into cryptocurrency through this exchanges. The clear warning to the ignorant ones Should be treat centralized exchanges as a marketplace, trade on them and take your funds back to your wallets.