SEC was pretty bad prior to Florida landing Spurrier. Many years Bama was the bell of the ball. It is a natural cycle.
The point is even when Florida was a barely bowl eligible team through a lot of the 80s, they still had elite talent like Emmitt Smith, Trace Armstrong, Louis Oliver, Jarvis Williams, Ricky Nattiel, Neal Anderson, Lomas Brown, etc. You don't have that kind of talent on the also-ran teams in other conferences.
And "prior to Florida landing Spurrier", the SEC finished with 2 teams in the top 10 in 1980 including national champions Georgia, 2 teams in the top 10 in 1981, 3 teams in the top 10 in 1983, New York Times/Sporting News/ etc. national champions Florida in 1984, 2 teams in the top 5 in 1985, 2 teams in the top 10 in 1986, and 3 teams in the top 10 in 1989. 5 different teams finished in the top 10 between 2 and 5 times in the 80s. (And I'm not including Arkansas as they weren't SEC at the time but they had some top 10s, too.)