I do think purity spirals exist on the right, but they are not as all emcompasssing as on the left.

You can be shunned from MAGA, while remaining republican. You can be shunned from the religious right, while remaining republican.

There is significantly more ideological diversity within the republican party than within the democratic party, and the result is democrats switching to republican at a rate 4 times higher than the republicans switch to democrats.