Yeah, but is there any indication that he wanted any promotion that would actually have made any difference?
Both Picard and Riker were offered promotions (Academy commandant was a RADM berth), but turned them down. If they were so all fired determined to keep Data at LCDR, they could have at least offered him a higher post and have him decline.
And having Deanna smugly tell him he vould cdll her "sir" was just rubbing it in, especially given that Data had more command chops in his android bottom than she had in her whole body. And... oh, yeah, saved the Federation a couple of times.
His approach to the Sutherland would have also been an equation, he was skilled and experienced and there was a need for his skill. He was even willing to assume that any racial prejudice was his own fault.
And he demonstrated that while he had some rough edges, he was a smart and capable commander. See "saved the Federation".
Getting back to Harry, it's hard not to notice that they were so careful to keep his canonical fate unknown. This is certainly because they simply could not justify keeping him at ensign after Voyager's return.
Ruining his career, yes. Although Janeway was out of line in reprimanding him (because he was in a mentally altered state), and he could have gotten it stricken easily, I doubt he would have... Janeway could have ordered him to slice his wrists with a rusty mek'leth and he would have done it, so keeping a career-killing reprimand was nothing. Still, his senior officer post on Voyager and his service duration would have gotten him at least a JG pip when Voyager got home.
Ergo, the only way to stop the "poor dumb eternal ensign Harry" crowd from pitching a hissy is to have him disappear from sight entirely after Voyager's return. Which is exactly what happened, aside from a few parallel universe copies (and we have been informed that none of them was "our" Harry). And with LD, PIC, and PRO over, it looks like that's a permanent thing.
