I don't know how much (if at all) this will affect Drake's album sales and touring revenue. But this could definitely affect his standing amongst rap greats.
But this dude has been positioned as a top tier rapper. Just look at the sprite campaign aligning him with BIG, Nas, and Rakim.
He should have just ignored it instead of having this 40 guy respond (via twitter of all things
).
By responding he's made things worse in two ways.
1st, just by merely responding, his camp acknowledged the accusation. This makes the claim appear more legitimate and less likely to go away as fast as it would of if his camp just ignored it.
2nd, the responses by 40 indirectly confirmed what Meek accused him of due to the fact he never denies it.
That's just my two cents.