I think, we, as pianists, all aspire to achieve different goals. Some want to become the top professional pianists, and would have to learn all of Bach's WTC and all of Chopin etudes and all of Beethoven Sonatas etc. which is needed for an all-rounded pianistic development.
Whereas further down the scale, there are some people who just want to play pieces that they love, without intending to develop maturity as a pianist. They would have a limited repertoire.
If monkeydudexd wants to be the person who just wants to play the pieces he loves, then why should we stop them? Unless he is planning to be a concert pianist or something of that sort, I think we should be encouraging him to learn the Appassionata sonata. Sure he may not be 'musically ready' or 'musically mature' enough do to so, but if just playing that piece is what he wants, then we should applaud him for embarking on this landmark composition.