when u open addons, there is an option to enable outdated addons.
Yes. Makes no difference.
I don't really blame the addon authors. It seems they have no way to coordinate with the devs so that a new update doesn't trash their addon.
This generally doesn't happen, and when it does, it's usually addressed pretty quickly by addon authors. For major patches there's the PTS which allows authors to see how it'll run on the next patch.
There was one minor thing with a new addon (Jack of all trades) where a change from PTS caused an issue, but that's actually abnormal.
Relthion: CP810 DK Tank - vMOL HM, vHOF HM, vAS HM, vCR +2
Malorson: CP810 Mag Sorc - vMOL HM, vHOF, vAS HM