In the short term, people will come by to lollygag. In the long term, there's only so much John Oliver anyone wants to see in a day, so traffic to those subs will likely fall.
My only hope this that this goes hand in hand with deleting posts prior to this. Leaving them up leaves them on Google and people can still interact with them.
Right now it's only giving spez a lot of extra traffic from people wanting to be creative and people wanting to see the shit storm. If people keep enjoying literal subs with shit posts, he doesn't care as long as he gets traffic and users before the IPO