alt Hacker NewsAndroid phones update to the latest version of Chrome for 7 years. As long as you're using browser features that are Baseline: Widely Available, you'll be using features that were working on the latest browsers in 2023; those features will work on Android 7.0 Nougat phones, released in 2016.
Android Studio has a nifty little tool that tells you what percentage of users are on what versions of Android. 99.2% of users are on Android 7 or later. I predict that next year, a similar percentage of users will be on Android 8 or later.
3.9 billion android users, means that 0.8% is 31 million people - and for a very small number of developers most of their users will be from that slice. For most of them… yeah go ahead an assume your audience is running a reasonably up to date os