Samsung fonts don't work in all apps in One UI 7 and here's why
Samsung released the One UI 7 beta 2 update and many users expected that Samsung fonts will be applied in all apps, but it didn't happen and here's the reason why.
Here's What We Know
The reason for this is due to a feature of the Android operating system that allows app developers to override system fonts. This decision helps improve app design and may not change anytime soon.
Third-party app developers have full control over the fonts used in their products and can either accept the system defaults or use their own fonts. It's an approach that allows developers to carefully consider every detail of the design.
Unless Google makes changes to the Android framework, this situation will remain unchanged. Thus, Samsung fonts will only be visible in the OS interface and Samsung apps, but not in third-party apps that override the defaults.
Source: sammyguru