Has anyone ever thought, or, has anyone in the botanical community ever suspected, that perhaps the "soft" and "hard" maples (or some other division thereof) belong in different genera entirely?

Aside from the leaf shape, samaras (the fact they both make them), and sap, for example, A. saccharum and A. saccharinum have relatively little in common for being genus-mates. They can't hybridize, have a totally different bud structure, etc, but I don't know at the DNA or chromosomal level how they compare.

I'd think Sugar, Black, and possibly Sycamore maple probably belong together, Red and Silver belong together in a genus, and the several "Japanese" maples along with Vine Maple are probably their own class as well.

Just my $0.02.