I made this change in response to a comment on the tracktype talk page from @Hufkratzer mentioning that the description of tracktype on the highway=track page was out of alignment with the tracktype=* page. My reasoning from the talk page:
I have changed the description of tracktype on the highway=track page to match the infobox on the tracktype page. I’m disappointed in myself for having made this error five years ago. The reason it happened is because at the time there was significant controversy around all highway=track being described as “unmaintained”. A major goal of that page rewrite was to remove mentions of maintenance because a road’s level of maintenance is not a good reason to choose highway=track as the primary tag. On this line, removing the mention of maintenance left tracktype described only as specifying firmness. I should have foreseen the misunderstanding this could cause. It was an unintentional oversight in a much larger rewrite of the whole page.
I figured to keep it short and be as neutral possible, it would be best to just use the same exact text as the info box description on the tracktype page. The text is right next to a link directly to the tracktype page where a longer description can be read. If all the recent discussions result in any consensus, then the info box text and this text on the highway=track page can both be changed.