Interesting so far...
I also don't use the drive regularly but when it comes to it, I'm glad I have it. I'd say my frequency of usage is about 2-3 times a month on average. Usually whenever I scan over my physical library of games and spot something I haven't played in a while and want to replay. I can play the game in minutes instead of hours (slow download) that way.
Regarding Blu-Ray, I haven't seen a reason yet to transition to it. It seems to be on the decline rather than anything else. Mostly movies are sometimes released on Blu-Rays and I don't usually watch them from discs anyway.
And once in a blue moon, I take a blank DVD and burn something on it. I still have like 200 blank DVDs that are many years old already, still untouched.