I’ve been told the sportster is a surprisingly good starter bike. The low center of gravity, and generally small size makes it easier to handle than most other mid-sized cruisers.
The big reason no one suggests one is cost. H-Ds aren’t cheap (not just to buy, but repairs if you drop it can be more expensive than some japanese bikes).
The other thing I hear about H-Ds is that the clutch and transmission are heavy adn clunky. To some people, that agricultural feel is part of the experience, to others, it is a big dissapointment (You pay for a lexus, but it drives more like an old F-150).
All that said, I’ve never rideden one myself, and H-D certainly has its own little niche of buyers (now there is an understatement).