I don't see it going mainstream for a pretty long time, not untill everything is made much simpler to buy and sell coins and pay with them.
Try to explain to Joe Smo crypto in short, making a wallet but is has to be safe, don't leave it on exchanges to dangerous, so many things to write down, but I guess you know it already.

Mainstream is not around the corner, I wish it was... but it has to be much easier to access before people drop there hard earned money in.