I had a male lab who constantly dribbled in the house his whole life. I had him neutered at 6 months (this was 16 years ago so I didn’t really hear much about later neutering, my in laws had breeding dogs and she was paranoid he would breed them). My vet always said it was because he was a farm dog and just peed when he wanted to, so he would always be messy in the house (I never quite believed that but I never looked further into it - I also have a new vet).
I have heard about incontinence on early spaying and females when I researched on when to spay my current pup. I did wait for her to finish growing and she had one heat when I spayed her (she was 1.5 years old). I really hoped she wouldn’t leak as she can hold it like a camel! Even at 8 weeks old she could hold it through the night and never had an accident in the house. And so far at almost 2 years old, she has been ok and has 0 issues there (so about 6 months after her lap spay). Its been so nice as I’ve had a dirty dog for the past 14 years before her, so this is a nice change. I never got mad at my guy though as he just couldn’t help it.
But its interesting about your guy. It wouldn’t surprise me if its due to early neutering.