She sure tried - that was the whole point. She had seen the future where Control triumphed, and wanted to undo that.
Why she failed was never made quite clear. There should have been obvious venues, including erasing Starfleet and mankind from existence if nothing else worked. Another time traveler fighting her would explain the failure - but we have every reason to think Control did not travel in time during S2 yet. Perhaps it gained that ability later on, subjective time, and therefore will always triumph and neither of the Burnham ladies has actually achieved anything yet?
In theory, Gabrielle could have tried to meddle, then decided to undo her meddling at every specific spot since it didn't pan out. In practice, he did save Michael's life at least once (in the shrubbery outside the Sarek mansion) and probably wouldn't have been strongly motivated to undo any of her other tricks, either. So the sum total of all her meddling is the timeline where regular Trek takes place.
Timo Saloniemi