"(...) struggle to form meaningful friendships/relationships with colleagues."
Whenever you're forced to do something, yes you will struggle. My colleagues are my colleagues. And if I like someone, I will bond with them and it might become a friendship regardless of whether i see them in person or not.
Still, I'm at work to work, not to make meaningful bonds. Using the word 'meaningful' in a work context makes the word almost lose its meaning and make it seem banal. Meaningful bonds happen by chance, and most people we come across with, we don't make meaningful bonds with anyway. And whether we want it or not, work environment is not the same as hobby or home or relaxation.
I have good friends, who i have meaningful bonds with, and I'm happy with that. At work, i'm getting paid to do a job, not to form meaningful bonds with people. I don't need those, because I have those already.
Maybe you enjoy interactions with colleagues, who don't enjoy interactions with you because they'd rather be home where they don't have to talk with someone they don't have or want a meaningful bond with.
And for the last point of "Sure, it might be technically more productive (...)". Companies try to make us believe it is less productive to WFH all the time. Remove that point, and there's nothing more on the table to want people at the office, than the fact that some need social interaction and to form meaningful bonds at work.
A few days/week of working at the office for people who want meaningful bond making could be arranged, and you all could connect with each other, sing kumbaya together, and make life long friendships then. Just don't force others to do the same.