I think regionalism was a little easier before mass communication was made possible. This is not to say that regionalism doesn't exist anymore. I think it does.
On a surface level, regionalism is gone, if we define regionalism as human culture. But, what if we define regionalism as something older than human culture?
Some of the best work that's happening right now is from architects who have remained in their home countries and who have focused on a local or national identity and the idea of critical regionalism.
I don't think massification and globalization and all those other 'izations' are necessarily hostile to regionalism.