It would be useful for animations that need to repeat frames a specific amount of times before moving on into another movement
example:Idle animation that after 3 cycles of the main idle the character look around or blinks,something like that.
example2: Running animation that after running for a while the character performs an attack.
ofc you can do this manually but it takes much space in the timeline and sometimes it becomes a mess,at least for me.
So it would work like that: You select the frames you want to cycle and then you put the number of times it is gonna cycle through it before moving on,on export it would just copy and paste the frames by the amount of cycle times you have put so it looks correctly,not sure how this would work tho.