Would be happy to see a support from open source community for LG phones long after the manufacture is closed. LineageOS for example does a good job supporting old phones. Reverse engineering takes ages and very often is abandoned somewhere in the middle of months or years of work. So it would be very nice if LG didn't push open source community to have to do reverse engineering.
Another thing is that they didn't manage to sell their mobile division so it means all their work is gonna go to waste. And that would be very pity. I would be happy to see them donating everything to organizations like Pine64 (or some other org - pine64 is just first that comes to my mind).
Most of the problematic parts that make it difficult to support into the future are from third parties like the chipset maker and the camera sensor maker etc.
OEMs don't really have what you'd need to make the phone "open", even assuming that they were legally able to.
Another thing is that they didn't manage to sell their mobile division so it means all their work is gonna go to waste. And that would be very pity. I would be happy to see them donating everything to organizations like Pine64 (or some other org - pine64 is just first that comes to my mind).