I was thinking about this today, since I'm close to finishing the game I'm currently playing. I think this year will end up being 4 games for me, though they're JRPGs so it takes me a while longer (and I usually try to 100% games I like)
Finish can also just mean play until you're satisfied too. So maybe a better question is how many games do you usually play each year?
As far as online games go, I'm also playing Splatoon 3 and Overwatch 2
I'd guess probably four or five. It depends if there are major releases I'm really interested in. I finish most main Mario/Zelda/Halo games. I also tend to replay random Halos throughout the year but I don't always finish them. I play through half life and half life 2 and the Portals every few years. This year I got into Spiritfarer which I'm probably an hour away from beating. I also started playing Cyberpunk again since I enjoyed the show but I doubt I'll make it all the way through again.