I posted in 2016 on this thread and basically said - yes guys like to see other guys cum.
I can speak for myself and whenever I am in the gym or at a nude beach I checkout guys' cocks- length and girth and if the guy is trimmed, shaved or has a full bush. I am bisexual so maybe that explains my curiosity. BUT, I would go on to speculate that even hetero guys are curious too about how they compare to other guys when it comes to cock size whether they see them hard or flaccid. Guys generally want to know how they compare to other guys. I should also mention, that hetero guys hardly ever talk about their cock size with their friends because they are sooooo self-conscious and insecure about the issue and would never want to get into a conversation about how they measure up. That would be terrifying for most guys especially young boys who are a few years into puberty.
Taken one step further, the comparison doesn't stop at anatomy but also with ejaculation. I would say when watching hetero porn, guys do watch and are curious about the amount of cum a guy shoots and how that compares to their ejaculation volume.
I think this psychological curiosity has its origins from guys being insecure about their cock size and wishing they had bigger cocks. I think if you asked guys if there was an easy way to increase their cock size, they would be all in. What we see in porn is not the norm even if it is homemade porn- the guys generally have above average size cocks and shoot large loads.
So again, I turn to myself. I have a 6-inch cock that is of average girth. Would I like an inch or two more length and a little more girth- sure I would. I would be willing to bet most guys if there was any easy way to gain extra length and girth, they would do it too. And the same goes for increasing their ejaculation volume- checkout the product call Semenax; their ads frequently pop up on all the porn sites.
Yes we do live in a world that makes us feel our bodies could be better or bigger when it comes to guy's genitals. The bottom line is that as of now you can only make your cock larger through injections to add girth and that has serious negative complications which are scary. So, the curiosity never stops, and we'll keep on looking and checking out other guys cocks but at some point we have to accept what our body looks like and focus on enjoying all the sexual pleasure it can provide with what you were born with. Keep in mind guys who have large cocks and shoot big loads are not guaranteed a better sex life. And maybe a huge cock at some point has diminishing returns when you consider it has to fit into an orifice that is smaller than their dick size.
Again speaking for myself, I don't know how many orgasms I have had in my life, but I can say I have never had a bad orgasm with equipment I was born with.