It seems to be the case that this recent resurgence in nationalism has had 3 stages so far. 2015-16 was the first time genuine nationalism started to get political traction. Then, the new parties that popped up or became popularized in that era started to lull in popularity upon people realizing that they tended to concede on various key issues.
Currently, we see an even more nationalistic response. Fratelli d'Italia gains popularity, political extremism skyrocketed in Germany, and explicitly ethnonationalist groups started popping up in the UK.

Another trend we're seeing is the popularity of economically left-wing movements as well. I feel that there's a significant overlap in people drawn to nationalism, and workers becoming exhausted by the exploitation of the global corporate elite.

Nationalists need to play it very smart in the current political landscape. Circumnavigating the political censors to reach their target supporters, avoiding constant attempts at de-platforming, and competition by 'false' nationalists and socialists.

As someone who's given up on the political process long ago, the tenacity and grit these nationalists have astounds me. They deserve all the support we can give them.