This might be less of an option then you'd think. Android software is often compiled assuming the CPU has comparatively recent instruction set extensions. Older devices, especially lower-end devices (which are more likely to be stuck on older software and more likely to be owned by people without the resources to frequently upgrade), might lack those extensions, making the app unusable. This is not a hypothetical. I've experienced this with FF a couple years ago (and even spent a couple hours trying to figure out how to build from source, but ultimately gave up.)
What extensions other than NEON are you thinking of? Neon was made a CDD requirement for Android 6.0, released on 2015. Even before that it was almost ubiquitous. The last shipping devices in any volume missing NEON were Tegra 2 tablets from 2011.
But good luck using it