Probably just timing and pacing reasons. The movie already spends an obscene amount of time on Tatooine rescuing Han. They could have easily done it with about 10 minutes of screen time and saved more room for the good stuff, which is the Luke/Vader/Emperor scenes. Which is why I’ve never been a huge fan of Episode 6.
Here what you’re saying, and agree with you but Idk if more might be less. Like the Luke v Vader v Palp stuff is so good, in part due to how well its paced, more might just add bloat. The issue ROTJ has is there is little to now act two, it goes from Tatooine to some lil scenes on Dagobah and Home one, then its stright to Endor and speeder chases straight into act three. Its bloated act one, truncated act two that make the film drag.