I don't know if Owner makes a difference, other than if they meddle in the operations of the team. Moreno has a once in a lifetime player in Trout and his management staff has made some decisions to acquire players to team with Trout that haven't worked out. Plus the Angels have been really bad at developing starting pitching, but that certainly isn't 100% the fault of management and even if it was certainly the Angels are not alone in that regard. Heck, the Brewers went a quarter of a century without developing more than 3 quality starting pitchers.
This is an over simplification too. Friedmann took over a squad that had just finished in first place and lost in the NLCS. He inherited Zack Greinke, Clayton Kershaw, Kenley Jansen Yasmani Grandal, Justin Turner, and Yasiel Puig. He also inherited several talented prospects: Corey Seager, Julio Urias, Ross Stripling, Alex Verdugo, Cody Bellinger. I don't think they really changed what they're doing. Their roster still is filled players who are amongst the highest paid in the game. The one thing Friedman did was hit a grand slam in the 2016 draft selecting Lux, Will Smith, Tony Gonsolin, Dustin May and Mitch White all in the same draft. To demonstrate Friedman's fallibility he whiffed on both his 2017 and 2018 draft.