I definitely think that ads will start appearing on the bigger instances especially since the overhead will most likely outpace donations. I could also see a lot of super small instances pop up just for people to host for their friends. I’m thinking about creating an instance just for me and a few friends but I’ll definitely have to deviate from my standard Reddiy username, can’t let that cat out of the bag.
I’m guessing a good chunk of people will be split between creating an account on Lemmy/kbin, raddle, squabbles and possibly tildes. One of the alternatives will most likely win out for users switching from Reddit, I hope it is Lemmy but who knows.