I think it's less to do with paying players and more to do with free transfers. The big time SEC teams (Bama, Georgia, LSU, etc.) were able to build incredible depth through recruiting and they generally kept those players bc of transfer rules.
Now, with free transfers, and the ability to get proven players paid, it is much more difficult for them to keep that depth.
That said, they still have far and away the most talent spread across that conference. I still think they stay as the best conference consistently but not as dominant as we have seen the last couple decades.