Can someone have too much knowledge or be considered a genius?

No. What everyone should try to understand is that “genius” with respect to intelligence is describing inborn potential. This is something that will either manifest into reality or not. Alot of factors come into play on whether or not that ‘genius’ individual will ever flourish and produce fruit, as a figure of speech. You have heard the expression: “Stupid is as stupid does” from Forest Gump, but you probably haven’t considered that genius is as genius does. The term genius in my opinion should be awarded on merit and not based on superior potential from birth. In this case, the more knowledge and training the better, however, there comes a point that knowledge needs to be put into action and if you spend too much time absorbing knowledge and not enough time applying it, the knowledge tends to fade and becomes less potent when you attempt to use it.