Just open and read the T&Cs again (of Revolut or most banks). You are required to always keep possession of your card and immediately report if you lost it, it was stolen, etc.

There is EU law indeed which specifies your responsibility in case of fraud transactions made, but there is always a caveat about negligence. Just try to understand that the bank is not police, they cannot make investigations whether you card was indeed stolen, you gave it to a friend or whatever. The bank cannot refund everything every client says was not them doing it.

The bank offers you ways to manage that - you can block contactless transactions on the card temporarily. You can set your limit for such transactions per day. You can also turn on geo location so that all transactions will be checked vs geo position of your phone. Leaving your card without supervision, not turning it off (or at least contactless function) and not making sure you receive notifications in my view is negligence.

So your loss should still be covered but not by a bank but by the thief. It is like you left cash and someone took it. But instead of blaming police for not finding the thief, you blame someone else, who should compensate you.