But as a user, my impression is that they don’t consider this feature to be existential enough to have a smoke test for. And I do.
And for a long time (I'm an early v1 user) what they did deliver was miniscule, ignoring a lot of the feedback from core users about basic issues. Some of the "new" features being released recently even existed in early v1 releases, e.g. the screen sharing which used to work fine locally, but now doesn't anymore because it "needs" to go via their cloud.
The break stuff unintentionally too though, so you're right there. For a few releases they even broke the core writing feature - lines and drawings would be drawn all jaggy - and the fix took forever.
The marketing worked and tricked me into buying one, but it's clear to me now that reMarkable is first and foremost a marketing company, tech and users come second. I won't be spending any more money with them.