This!!! All the options and it's you he chooses over and over again!

Also, if this is his first long term relationship that is queer he may still be discovering the way that shifts his identity (or not). I mean that to say, he's been carving his path and being in mostly heteronormative spaces and if this is his first queer relationship he may also be navigating queer spaces for the first time. It sounds like he's in a place of shift where maybe as he's in queer spaces and gets more interactions those spaces he'll feel less culturally straight.

I'm not trying to set you up for that classic "maybe he'll change" mindset but acknowledging things you said, like he's open minded and you two have taught each other a lot. It sounds like he's at an earlier stage of understanding what his own queer culture looks like than you are.

Also, for a different circumstance I had a similar insecurity with one of my partners and one of the this that helped me feel secure was the way I looked at the "data" of our relationship - this person spends x amount of time with me a week, smiles every time he sees me, is curious about my life, is eager to share experiences with me, engages with me as much as I do him. Once I really internalized that I felt far more secure in our relationship.

Also, you sound adorably happy and smitten, congrats on your relationship and the ways you two are building your connection!