Any attempt to 'fix' culture at this late point will be generational. You're right-- it will take extra generations if it doesn't start at the educational level. The time spent mustering power elsewhere, just to spend the necessary effort gaining control of educational institutions, will be spent by our enemies further shifting the Overton Window to the left. Every graduating class has been more leftist for about a century now. Just to fix the damage done since the 50s by the radicals of the 60s will take sixty to seventy years from current year plus however long it takes to gain the political power to start the process of course correction.

A cultural collapse from these parasites killing their host before we can even regain power seems more and more likely.

Because of the time spent waiting for 'the pendulum to swing back,' we're looking at a cultural field so slanted that parallel institutions forcing direct ideological competition will be faster than the political siege necessary to uproot the ideologues who have taken over education. Hell, traditional westerners might never again have enough political power to effect change on the academy. In that case, parallel institutions might be the only viable strategy moving forward.