It's really difficult to give you a useful answer. Some teams have succeeded and some have failed. It depends on the product, the team, and the user base. I've built and worked on both native mobile apps (swift and kotlin) and cross platform (react native and flutter). Personally I would choice native and have for my projects. That being said I personally hate the JavaScript eco system and language so to me it slows everything down. I'm faster (not twice as fast though) and much better in the native platforms. That doesn't mean your team will be. Who you hire and what the product is will matter more than which tech you use IMO.