That is very true. The elite programs offered crazy upgraded facilities and various perks and the best coaches as non monetary compensation because they couldn't pay the players. Now that is moving in another direction.
The NFL may not have ultra nice facilities, but they don't seem to scrimp on coach salaries:
https://sportscriber.com/money/nfl-coaches-salary /
Right now, the highest P5 coaches are in the same range as the highest NFL coaches:
https://www.nbcsports.com/chicago/college-football-head-c... It's reasonably to expect that, at the high end, P5 salaries may drop to well under the NFL salaries as more money goes to players. How much, if any, effect that has on the lowest paid coaches, such as Albin, remains to be seen. This is from 2016, but if you adjust these for inflation, FCS salaries are not far below the bottom of G5, so I don't think the bottom salaries will fall much, if at all.