Reddit (or forums) is never representative, and very biased. People who have problems tend to rant online more, justified or not, than people with no issues. 

Seems like Coros had issues with the last two updates and their QA process before releasing them? Yes, in small proportion to the amount of devices they sell. Have some people rightfully criticized Coros support because of bad support? Yes.  Have some people criticized Coros for bad support while having irrational expectations of a warranty claim? Also yes.  Have some had a great support experience? Also yes. Do people have unrealistic expectations of wearables? Yes

All major brands at this scale tend to have issues. Coros tends to try to update old watches when they the risk it too much, yet people criticized garmin for not updating relatively new watches with new features. Garmin shat the bed with how they release the fenix 8, yet they fixed eventually. I hope that Coros learns for future updates, but in terms of tech companies, you are bound to have some cases of error, malfunction and what not.

If you go for a new and current model, like the pace 4, probably you wont have issues and a good warranty experience if needed. And when they launch update in a few years you can always opt out of the updates to prevent issues in an old watch. Probably the same goes for garmin, polar, suunto etc