That is a fair concern, but I can assure that won’t happen. We have people dedicated to the laptops, and we’re hiring more, and they don’t work on the phone at all. PureOS is getting a lot of attention at the moment. Not least in the tooling around PureOS.
Regarding GNOME 3.32, we are targeting that as a version of GNOME we want. As Debian’s Buster becomes more stable, there will be greater stability in the operating system that is PureOS and one of the less stable parts is GNOME.
Can you point out what crashes you’re seeing? My machine, which I use daily in heavy usage and is stock PureOS, doesn’t crash. I keep it updated and run a bunch of cutting edge GNOME code via flatpak, but I just don’t see a lot of issues when I look in dmesg or my logs. Please report what issues you may have.