From what I remember, it was actually Akiva Goldsman who did the majority of day-to-day on Picard season 2. Both he and Matalas are credited for season 2, but reportedly partway through production on season 2 Matalas turned everything over to Goldsman so he could prep Picard season 3.
Also, I feel like this can be seen in some of the tone changes between seasons 1 and 2 of Strange New Worlds. Goldsman and Henry Alonso Myers are credited as co-showrunners for SNW. But day-to-day for season 1 was done by Myers, since Goldsman was busy with Picard season 2.
For season 2 of Strange New Worlds, though, Goldsman and Myers ran it together, and Goldsman had more of a voice. And I think you can see it in some of the choices and the tone compared to season 1.