I tend to agree that 'parity' is an annoying buzz word and that the reality remains a bit sparse on the ground. AZ in the championship game follows along with Louisville (twice), Syracuse, etc. in terms of surprise FF teams showing up over the years - as well as surprise losses by 'mighty' teams before the FF.
I do think there are two issues that make a difference in the current era - better quality coaching in the women's game at all levels and the quality and wider dispersal of HS talent.
The era of a sub .500 coach having a 25 year career at any college is at an end and the pay level for women's coaches has made it an attractive career for more people. And the pay level at the assistant level makes it a better than subsistence option for those starting out. This is attracting more quality coaching to the sport and therefore more quality team play and player development. The old exhortation of hustle. heart, determination and rebound!' doesn't cut it any more. (The WNBA/International play is also creating a larger pool of well coached players who may choose to continue in the profession when playing days end.
As far as number and quality of the players - there are still only a few 'superstar' players coming out of HS, but they have more quality coaching options at more schools that are actually invested in WCBB than there were 10 or 20 years ago. And the rest of the top 100 recruits have mostly spent more time with quality coaches, trainers, and players than ever before. Geno and others may complain about having to teach more team concepts, but individual skill levels are I think also better than ever. While only a few coaches ever get a Breanna Stewart to coach, a lot more get a few Olivias, Christyns, and Evinas to work with.
The 'parity' that everyone touts in the men's game and complains about in the women's game is based on the 1 and done world that exists there - unsurprisingly the 21 year old players at the mid-level colleges in men's basketball often outplay the freshman filled teams at the 'power' programs. UCLA's streak was built not just on incredible talent, but also on a locked in four year development for the players and a year of coaching freshmen before they could actually play a varsity game. Change the rules (and enforce recruiting rules) and dynastic ambitions last all of 12 months.