It's too early to say. I'm assuming you mean Standard, where Reality Fracture released on 2026-10-02. Only one Dragons vs UW Control match has been recorded since then.
That match was Boros Dragons against Azorius Control, and Dragons won it. One match tells us nothing about the matchup. The data only runs through the first weekend of Fracture events, and only two Standard Challenges are in the database for that window.
For a baseline, here is Boros Dragons vs Azorius Control from the Hobbit release (2026-08-14) through the day before Fracture.
So before Fracture, the matchup leaned slightly toward UW Control, but not by much. Check again after a few more weeks of events.
Sources: Data from 2 MTGO tournaments in the post-release window (100% MTGO). The baseline comes from the Standard matches table from 2026-08-14 onward.
https://www.mtgo.com/decklist/standard-challenge-32-2026-10-0212855471
https://www.mtgo.com/decklist/standard-challenge-32-2026-10-0212855466