Clients usually ask about Flutter expecting the pitch to be development speed. That's real, but it's not the biggest saving. The bigger one shows up at the second and third release, when a single codebase means one QA pass and one release train instead of two.
The tradeoff is platform-specific polish: camera handling, background tasks, and native gestures need deliberate attention or the app feels generic on both platforms. We treat that as a checklist item, not an afterthought.
For teams shipping to both app stores on a regular cadence, that consistency compounds. For a one-off app that never gets a version 2, it matters a lot less.