I agree with you, it’s really difficult to tell on many of the smaller grass airports and they should do something to make it clearer. I’ve noticed on some they have small white corner markers to show the corners of the runway, but they’re so difficult to see I’m rarely able to see them even when I’m on the runway itself.
My main point was that whatever algorithm they’ve used to zone runways and taxiways is making some massive gaffs, so it doesn’t even matter in many airports where the runway is still clearly marked and visible, the sim still doesn’t recognise it as a runway because it’s been interpreted it as a taxiway or ‘empty space’…
I’ve made many landings, centre-line of a clearly marked asphalt runway, and the sim thinks I’ve landed on a taxiway for some unknown reason.