Seriously--I used web wallets when I was first playing around with bitcoin years ago, but at this point I don't think anyone ought to be using them when there are much better alternatives (like Electrum). At least with software or hardware wallets you don't have to worry about situations like what OP is describing.
I have used desktop crypto wallets from the beginning because I have learned that anyone who does not control their private keys does not actually own any cryptocurrency. But that doesn't mean I didn't want to try the service we're discussing here, and I've had an account there for years without any problems. For many beginners, alternatives such as desktop or hardware wallets are much more complicated than opening an online crypto account, which is why such services have a very large number of users.
The situation that happened here can also happen with hardware wallets, in case the user uses an application through which he has access to the
blockchain. An example is Ledger Live, if Ledger servers go down that software becomes useless, at least when it comes to receiving and sending transactions. Of course in that case there is an alternative to using another UI - but such option exists in blockchain.com - just use your seed with some other wallet and you have bypassed the problem.