I feel like there is a seed oils as immersion miner coolant fluid play out there somewhere

Seed oil got grandfathered into GRAS because they were in US foods before the regulatory regime started.

The marketing is largely Ansel Keyes & the vegetarian diet doctors (many of whom have religious or ideological convictions promoting vegetarianism). They vilified saturated fat & had to promote something else. Another key proponent was USDA, who was tasked with promoting produce and then with setting diet guidelines. Shockingly, the one task influenced the other.