I feel Bama was good due to having great coaches and trying harder than most other schools. And once the momentum got going it snowballed. I’m 43, so I didn’t experience the Bryant era, and before Saban, Alabama wasn’t really on my radar. In the 90’s Miami, FSU, Florida, Tennessee were the big southern programs.
Bama and Oklahoma are maybe comparable to me. Football has been very important to both schools and they put more effort into being successful than pretty much all their peers. At one point, both states wanted dominant football programs to instill pride back in their residents and legitimize their boys nationally. Both programs have had multiple legendary coaches, maybe due to luck or maybe due to great management (or both). But, neither program has inherent geographic or financial advantages. Both states have good talent, but not top tier. They’re adjacent to top talent producing states. Neither school is particularly rich or unique. The NIL game will really change things for the schools with the really big buck booster, so long as they have competent coaches and administration.