Besides the fact that he can smoke more than omen/clove, what makes brim so viable on fracture? why do teams opt with him over omen for example? On defense, how do teams not get baited out of their smokes, etc?
The downside of Omen in general is that his smokes are very slow. Brim can drop smokes and stim and run in, but Omen smokes take a critical few seconds longer where you're giving your presence away and aren't gun-out with the team.
Similarly, Astra can pre-place a star and flick to activate it when needed, whereas Omen needs to be firmly behind cover for a few seconds to smoke for the team.
The shape of Bind and Fracture is also such that Brim molly and ult clear a lot of space. Tejo and Breach are more "expensive" to run, in the sense that they need another initiator to help with scouting, which in turn prevents you from running double smoke, double senti, etc. so having high delay power on your controller is efficient.