Now, when bitcoin transaction fees are ridiculously high and no online wallet would be able to pay them for their users, there is no need to use Xapo anymore.
Why do you need to use Xapo when there is mobile version of Electrum available in the first place.
Fees are important but they are not the only factor at play here
Web wallets provide ease of use, but please don't tell me that desktop wallets are as easy. That will never be the case. You have to install them, you have to back up them, you have to learn them, after all. With web wallets all these things are hidden from the user and done by someone else. The user just needs to remember his login and password, and if he uses Internet, this is what he is already used to. I don't even mention the security of web wallets. Yes, they can scam and they can get hacked, but I'm dead sure that an average user cannot secure his desktop to safely use a desktop wallet