You can do a lot better than a lot of the Nest hardware, but my personal opinion is the Nest Protects are worthwhile, connected or not.
I’m using this as a temporary solution until the dust settles around the Google Nest fiasco. If you kept your old Nest account and you’re an iOS user, then this could work for you too.
Honestly I think they’ll get their act together eventually, so I would not suggest making a lot of major investments in new equipment just yet. Give it more time. CES was a big platform for them two years ago, and it drove a lot of sales. So I would guess they would try to rebound in time for CES 2020. Black Friday can be a good time to replace duds, but it might be a bit premature to count them out at this point in time.