my opinion
Bitcoin is Not Mainstream Yet because :
1. we need more advertise about bitcoin,not all of debt card user know about ease of bitcoin.
2. not many bitcoin user have pleasure to introduce bitcoin to their friends or family.
Marketing is not really needed at this point, we still don't have a clear way to scale Bitcoin. If marketing was a big success and a ton of people became adopters all of a sudden we would have big problems dealing with the new amount of Bitcoins. I think it's better to stay low key until all thinks are clear scaling wise.