Maybe. The Highway 407 GO routes have a fair amount of combined potential. I've seen estimates at the 10k mark for peak hour ridership in 2031 with a very high %age of those transferring to the Spadina line; a little over 1 double-decker bus per minute, so it's manageable.
It's an MTO project which is why it's kinda flying under the radar:
http://www.407transitway.com/kennedyToBrock/projectBackground.html
501 Zum Queen route from Brampton also has substantial growth potential over a 10 year period if some kind of fare cooperation occurs to reduce the TTC hit.
Both were intended to terminate at this subway station and no longer on York University property; this plan may have changed.
So, in the short-term, no, but it could be relatively busy in a decade.