Hi, no worries. In general, it is best not to survey/tag things in winter that are impossible to determine. But if you are local and you know the surface, then that's fine. On aerial, these look like typical dirt informal paths.

Ground is more generic that dirt. It just means there's no man-made surface. For example, in a forest you might have a mix of grass, dirt, roots, pebbles, leaves, moss, etc. - so it's not really possible to say what one thing it is exactly. While specifically dirt is just the exposed earth layer without vegetation. It's rare in cities to have actual recognisable grass paths - they get quickly stomped out.

In the case of real-life dirt+grass mix, I would still put it as dirt, because that's the surface that indicates the path through the grass and differentiates it from the surrounding grass. Personally, I just leave it as ground most of the time exactly because of the question you ask. It's never going to be precise for these informal paths that are just exposed and stomped dirt lines through what used to be grass. I just recommend not putting specifically grass, but both generic ground or more exact dirt is fine.

The problem is that you are mass editing all over the world without any discussion with a vague changeset comment and apparently only to quiet down a validator warning. And you are still doing it despite the comment above. Where has it been decided to mass insert nodes to long ways? Which "practical constraints and community standards" are you referring to?

How are you determining the surface of these paths in the middle of winter with snow cover? How do you know this is grass and not dirt/ground?

This does not look like a handlebar holder type parking, this looks like typical frame-supporting stands.