Iga has now won a final from a set down, which she has never done before in her WTA career.
I had to look that up, because that seems unbelievable, but here's the data :
She's lost 2 finals in straight sets, and 3 in 3 sets, in all finals but one, (Ostrava 2022 vs Babs) she did so after losing the first set.
She's won 21 (!) finals in straight sets. 3 finals in 3 from 1 set up and just 1 final from 1 set up.
That's a finals set win-loss record of 53-14 (79.1%), assuming each set is independent (the formula being 3x^2-2x^3), she'd be expected to win 88.7% of her matches, or about 27 of them, in other words, she's been
underperforming compared to my naive hypothesis, so when she was winning, she was usually winning by a lot.
By comparison, Serena was as follows :
48 straight set wins, 24 3-set wins, 16 straight set losses, 7 3-set losses and 3 walkovers/retirements (not counted). For an overall win-loss of 151-70 in her sets (68.3%), and an expected 76.3% win-loss, she actually performed as predicted 72/95, or 75.8%), which suggests a sample size issue for Iga.
TL

R Iga is winning more of her finals than Serena.