1) Going forward I believe the Gnome guys see anything that's not libinput as unsupported. So we could log an enhancement request to get them to add Xorg synaptics support (ie. tweak the same things as 'synclient' does). But they're likely to ignore that request. Still, I think if someone could implement it based on the synclient code, they might accept a patch.
2) This is certainly a problem and what we should be fixing (although I haven't tested upgrades myself to verify). Let's make this bug about the upgrade problem.
You make excellent points.
1) Going forward I believe the Gnome guys see anything that's not libinput as unsupported. So we could log an enhancement request to get them to add Xorg synaptics support (ie. tweak the same things as 'synclient' does). But they're likely to ignore that request. Still, I think if someone could implement it based on the synclient code, they might accept a patch.
2) This is certainly a problem and what we should be fixing (although I haven't tested upgrades myself to verify). Let's make this bug about the upgrade problem.
Thanks for persisting and figuring it out.