Never had any SSD fail in my life ever. This is a worry for some, but its not a realistic fear. You can write TB daily to most SSDs and it'll still not wear out. What's your current SSD's usage written in S.M.A.R.T.?
I don't disagree with backing up, but you don't think that will repeat again do you? What brand was it? It sounds like one of those cheap $19-$25 128GB ones with no cache and made with the worst quality, was it one of those? Cheap SSDs are notoriously low quality and unreliable.
I'm not sure what else to say. I know that SSD fail from direct experience. This doesn't mesh with you. I get it.
So yeah a Mac or other device with a soldered SSD is less trustworthy.
I'm not even talking backup as best practice or some good idea. I'm actually saying that due to this pattern of unreplaceable SSDs, the cloud copy IS the primary copy. The local copy on SSD is now just a cached file. That is a very big difference.
This isn't even an Apple thing. But they are one of the first.
I'm very suprised, I believe you, but I never had such an occurance happen ever to me, and I never worried once about it. Not even my cheap free android phone NAND failed in such a way, and I was given a microSD that had write disabled but had all the data left to read off it (not my data didn't care about it), but I never had any bad experinces with flash memory in my life.
One was a windows box with a generic Kingston 480GB.
The other was in a 2014 MacBook Air.
In both cases, both completely dead with no data recovery possible.