I was rather happy with my old, dumb Roomba. It just bounced around until things were clean. No cloud required. No mapping. No AI marketing foo. Seems like all the newer alternatives want internet access and send maps of your premises to some cloud somewhere. Seems completely unnecessary to me.
I still have one like that, and it runs mostly fine, but is partly held together by duct tape these days. Not replacing it as long as I can keep it running.
Especially considering that story some year ago about photos taken by Roombas that had been uploaded to the cloud and leaked.
https://www.technologyreview.com/2022/12/19/1065306/roomba-i...
Mapping is very useful. I get the want to safeguard your data, but having smart navigation and obstacle detection just makes the product better.
You can still find ones that don't need to be registered online and will work without WLAN or app. They will not remember the room layouts and you won't be able to lay virtual fences, but apart from that they work fine.
Roomba couldn’t remember map, so when you wanted to clean part of the apartment you had to build barriers or just walk with it. It also got lost way too many times.
As for the Chinese products - look at Valetudo. If you write about cloud and privacy considerations then you are already aware enough to just flash it and you have local, cloud-free, GREAT product.