Earlier quoted context omitted.
Definitely not all live and functioning. In fact I suspect less than 10m are actively used. It is a company that has been around for years and it has run into sales issues that last few years with competition and their products have tech product lifespans of around 3 years I suspect.
Personally, I have a Roomba I bought in Jan 2019 that's still doing just fine (So 7 years now). Most of the parts are pretty easily replaced (genuinely pleasant surprise, as an aside) and the company stocked most replacement parts for a long time - I just checked again and I can still get parts for my model (I-series) incl batteries, wheels, brushes, filters, etc. Which is less than it used to be, but still enough to…
Mine is from 2017 btw, still doing daily duty.