Realism goes so far when dealing a superhero story haha
I think it's just normally a given that at least one or two pairs (or three with this cast size) will end up canon for these types of works. And many people do marry high school partners or crushes (staying together is a different story lol).
I'm with you though. I hope Deku can get to #1. I feel like he's the only that didn't get a huge reward post-war (that we can see). May be because he left the spotlight because the kid at the end does know him. Just wish it was shown more (like give him a statue next to all might because COME ON HE'S MORE THAN EARNED IT)
Horikoshi did an 8 year timeskip to completely remove their association from high school because its the *end* of my hero *academia* and he solidified that with Deku working as a teacher and then becoming a hero again and other heroes competing against eachother for spots of the hero ranking list despite being friends. I don't think he wanted any one to date. Momo and Todoroki never really were written to be a couple after the beginning chapters of mha, Kirishima and Mina are just friends with a shared past, and Ochaco literally spent such a long time trying to get rid of her crush on Deku so she can focus on her self and people only mention her name in relation to Deku. Tokoyami and Tsuyu never really hit it off like that. Jirou and Kaminari are just friends who love to goof off together. I understand the appeal of shipping but none of them were ever intentionally written to be in relationships.
People are mad at the ships not being fulfilled but no one is going to realistically date/marry their crushes from high school in all honesty, especially when you're busy saving the world from the age of 16. They're all 25 now and competingwith each other for ranking. I just hope Deku goes back up to number 1.