>I don't see any reason to think this is accurate.

We are living through a successful attempt at this right now. The Tea Party completely engulfed what was once the GOP and morphed into MAGAism. Sadly the progressive wings of the Democratic party never got the memo, and wrote them off until it was too late.

The Democratic party does its best to isolate their more "radical" voters and politicians and does whatever it can to try to appeal to whatever their consultants tell them the "median" voter is. The Republican party embraces its most crazy elements from the depths of Twitter and puts them on a national stage.

How is that an example? That's assuming that the Tea Party has good ideas and that's why it was able to take over the Republicans. It may very well be that the Tea Party's success had nothing to do with the merit of their ideas and more to do with an expression of rage.

> Sadly the progressive wings of the Democratic party never got the memo, and wrote them off until it was too late.

Eh? They've never meaningfully had control of the party, and are surely far more willing to e.g. abandon neoliberalism to avoid that handicap vs. a MAGA-ified Republican Party that's abandoned neoliberalism, than most of the rest of the Democratic Party is. It's the 3rd-way sorts and "centrists" who've been, and remained, in charge of setting direction and who've just kept on trucking with the "we mustn't upset the status quo!" and "maybe courting traditional Republicans will suddenly start working, so we should keep trying that" strategy, no?