I have been using cairo-dock for quite some time now and I realized the bottom bar wasn't showing when I hovered over it previously today, I then went to resouce manager only to find out it's not running, proceeded to check software center and not only is cairo-dock no longer installed, I can't even seem to find it with the search function. Is this because of the recent switch from BZR to Git, or something else?

It's been deprecated from the repo. It hasn't seen a release in years and I can count the amount of times a git commit has been made against it for years on a single hand. It is not actively developed, nor are its plugins.