Honestly had never heard of 'age gap movie'. I dunno why that would even be a marketable concept. I myself am in a fairly spacious gap of 6.5 years which has its own notable issues, but I wouldn't say movie-worthy as a concept lol.

The ones you bring up just make me feel weird knowing they exist. I have a kind of suspicion that most movie directors touching on touchy subjects are themselves a but suspect. Call me judgemental or whatever lol but I just get that vibe (and a non-zero percent of the time I turn out to be right)