I had a female science teacher in middle school who was 6'5". And there are women who meet the seven foot space marine requirement. Such a standard would not necessarily bar %100 of women, just 99.99999999%. Plus humans have been getting progressively taller over the last 150 years or so if you add that to the differences in gravitates and such on other planets, a seven foot tall height requirement for space marines might not actually be that crazy by the time “space marine” becomes an actual job. Especially if we add some genetic modification to allow humans to survive on different planets.
I’m a military science fiction buff.