I was just making the point that litverse or not litverse, close to 20 years after making captain it would be reasonable that he would be an Admiral by then.
Not necessarily. Trek fans -- and often writers -- seem to assume that every single officer who starts out as an ensign will eventually get to be a captain or admiral. But that's not how the military works. Any officer is responsible for a large number of people of lower rank, so the higher the rank, the fewer openings there are for it.
Here's a list of the number of active duty officers of various ranks in the US Navy as of a few years ago (if I'm interpreting the meaning of the site correctly):
https://www.navycs.com/blogs/2013/04/11/2014-projected-active-duty-end-strength
Out of all commissioned officers, about a third are lieutenants, and only a fifth are commanders or higher. There are half as many captains as commanders, and a fifth as many captains as lieutenants. And there are only about 7% as many admirals (of all ranks combined) as there are captains. Which means that 4 out of 5 lieutenants will never make it to captain and 13 out of 14 captains will never get to be admirals, because there just aren't enough openings.