My truck could use a seven speed manual transmission. It's six gears are decent, but if converted to a stick it would need one more for a granny gear. And then perhaps a two speed reverse, or just a stupidly low reverse.
My Camry has six gears, and I haven't a clue what they were thinking. There might be a 100rpm diff between 5 and 6 at 70mph.
Actually, iirc, doesn't the EPA test cycle not allow downshifts from top gear? Maybe it does, and it's the OEM that gears top gear stupid short so consumers won't have to downshift.
Done right six gears can be nice. Done wrong and it's no better than a five. And my Camry is no better than a five. Pure gimmick there.