If you create a GLES3 project, the
AndroidManifest.xml file will require OpenGL ES 3.0 support. That means that any Android device which does not have OpenGL ES 3.0 drivers will not be able to install the game at all - it will be shown as incompatible on Google Play.
The main issue you're alluding to is that a significant proportion of Android devices have OpenGL ES 3.0 drivers, but their drivers are very bad and can crash when some OpenGL ES 3.0 features are used. They're typically lower-end phones with chipsets like Adreno 300-something.
For those it's tricky, as the device reports OpenGL ES 3.0 support, but in practice their "support" is so bad that it's not usable, and it would be better to use OpenGL ES 2.0 on such devices to be safe. There's no easy way to detect that, so if it's important for you that the game runs on as many devices as possible, you should use GLES2.
Note that GLES2 has Glow support since Godot 3.2, so you should be able to use that: https://docs.godotengine.org/en/stable/tutorials/misc/gles2_gles3_differences.html#environment-features