Cowboy went 5 once and then 6 times in a year, which I believe is a UFC record. But that's Cowboy. Volkan made his UFC debut and fought DC for a title within 4 fights in 12 months, Cody Necktats went 4 in a year - from unranked to champ within 12 months. Smith is about to have his 4th LHW fight within a time span of a year vs Jones... Conor also averaged 4 a year in early UFC days - Aldo, Diaz 1, Diaz 2 and Alvarez being the most stacked run. But wait, sorry, why I am I mentioning all this like a nerd...
Your point was that fighters aren't as active and it's true. It's rare to see even 3 a year. Stats seem to show that activity leads to belt contention, though, so maybe it'd be wise to step it up.