People buy Gsync because they have Nvidia GPUs so they need Gsync if they want adaptive sync. That's no longer the case. The minimum quality of Freesync is a lot worse definitely and there are lots of legitimately terrible Freesync monitors out there, but that shouldn't matter if you do your research and buy one of the ones which aren't.

A good Freesync implementation is just as good as good Gsync; the 34UC79G-B is actually better than the Gsync version, thanks to it's native 144hz refresh rate whereas the Gsync version of 100Hz out the box and 120Hz OCed. I've got Gsync myself and it's nice, but not worth the premium and if I'd known this was going to happen I would've gone Freesync instead.

Also HDR on monitors is either terrible or expensive and mediocre.