Allow me to try to answer that coz I had the same question. I had the same games in addition to dirt rally, Sebastien Loeb etc...
What helped me to change is the following:
-I wanted a higher fps.
-I wanted to play the highly rated games like Rfactor2, Raceroom, Automobilista, iRacing etc... (at some point in the future)
-I wanted to play all of these games in pure VR (not demo VR of GTS).
-Or I wanted to be able to play all of these in triple screens.
That alone warranted the change for me. I now play all of these in VR and trust me racing a whole field in VR in AC or PC2 is just majestic...
I didn't mention the huge number of mods (I have more than 100 tracks on AC and more than a thousand cars...).
I didn't mention all kind of hardware compatibility (mix and match any wheel with any shifter with any pedals...).
I didn't mention the "CrewChief" app that is amazing.
I didn't mention the huge number of accessories, add-ons, and madness you can do on PC.
Oh, did I mention VR?!?