If you had a bunch of things timed to be taken from a charge account, and you exceeded your credit limit because some sort of fraud or double charging happens, identical chaos would ensue.
edit: and there's certainly not a vast difference in carrying $20K of credit and $20K in cash. We live in a world of negative interest rates.
The problem is errors are random so your 'solution' is to keep huge amounts of cash in your checking account to deal with random error.
But, if I max a CC I would still have the cash in my checking account to pay other bills. If I don't have a CC and my checking account is empty I am going to have issues paying rent etc.
PS: Think of a CC as a financial firewall. You still need the cash to pay your bills, but keeping a redundant CC with an unused 15k credit limit is cheap.
Case in point. I had a two-week hotel stay and facility booking at a resort on my AMEX. The hotel fucked up and double-charged me for the event -- to the tune of $20,000. Due to their obtuse bureaucracy and overall stupidity, it took two weeks to get the issue resolved.
In the debit card scenario, I'm stuck with a $20,000 liability immediately upon the hotel screwing up. I don't keep a five-figure balance in my checking account, so that's a problem until I notice that this event has happened. (Which I may not, because I'm on the beach enjoying my honeymoon and not checking my mail).
With the credit card scenario, I get back from the event, open my mail and discover a $40,000 bill instead of a $20,000 bill. Nothing is bounced, everyone is paid, nobody is angry at me. I make one phone call to AMEX, dispute it as a double charge, and my risk (and work) is done.