Author here! I think if you're just concerned with efficiency (speed/low overhead/etc) centralized solutions will always beat decentralized ones. The key advantage you can get with CRDTs — and, more generally, decentralized applications — is stability. By which I mean: Figma and Google Docs are great, but they can go out of business or delete your account or up their prices, and everything you've poured your time and energy into making just vanishes.
It's not just this way for collaboration software. Servers make everything more brittle. A few years ago, I tried to restore every website I've ever made. Static files were easy, things that relied on old versions of server-side languages were harder and anything stored on a server or in a database was just gone. That sucks. I want us to be able to keep our memories forever, not lose them because we stopped paying a hosting bill.