Anyway, back to the subject
I think that only working photographers 'need' FF, where clients specify it, whereas some hobby photographers might 'want' FF to get the very best out of their interest/hobby/all-consuming passion/waste of time and money.
Telephoto lenses seem to be more or less OK with FF or cropped sensors but there are still questions over wide-angle lenses in FF yet Canon don't seem to have done much with their range other than improving a couple of WA zooms. With prime wide angles there are just the old film-based designs and any optical defects need to be corrected with third-party software. I must admit that I've never seen any photos,
first hand, taken with wide angles on FF cameras - perhaps the problems are more visible in test situations rather than 3-dimensional real-life photos.
(Incidentally, wouldn't the renowned 'tonal gradation' of Minolta lenses be actually
better in digital cameras than the higher contrast Zeiss optics? - Just a thought
)