The first night I spent the whole night with my third long-term partner, when I was 32, I came 5 times in 10-12 hours--and we weren't trying to set any record. Just a few months ago, at 43 with my fourth "ex," I came three times in 8 hours or so--and wasn't trying to set any record. (And I'm one of those guys for whom orgasm=ejaculation; I've never learned how to do one without the other.) In fact, I've never tried to find out the maximum number of times in a day or in 24 hours, even when I was a teenager or college student.
I've had friends (current and former) who have told me that they couldn't cum more than once a day, and even one who couldn't cum twice in two consecutive days, by the time they were in their mid- to late 30s. I think that's unfortunate and certainly not my situation.