We've always had wealth at the top, but the top was defined differently. How many teams in each conference had a realistic change of a top five finish? Three or four, and at times an outlier would break through, just as Washington did. Georgia was an outlier last year to some extent starting out ranked about 15th.
It starts with recruiting of course and finishes with coaching, and some luck at times. The teams that make the playoffs have recruited really well, not top ten, but top five, most of the time. That top five in recruiting doesn't vary much year to year, and the top five in the polls don't vary much either.
I can't pine for the halcyon days when only Notre Dame, Michigan, and Army had teams with a shot.