But it IS a "sliding scale."
Team with a winning record is not a static stat until the season is over. It's in flux throughout the season.
The Jets are not a team with a winning record because AT ONE TIME with a tiny sample size they had a winning record. They're a 5-8 team. Factually, they are not a team with a winning record. The fact that they happened to start 1-0 doesn't change that (unless they win the last 4).
Technically, at week three, you can never say you've beaten a team with a winning record, as the best record they could have at that point is 1-1.
It's what the team is, not what they were at some random point in the season.
I'd agree it's a silly thing to look at, at least until late in the season, as it's something that's constantly in flux, and because of issues of teams near .500 and how the game with whichever team the argument is being made against turns out (lose to a 6-5 team, and you lost to team with a winning record, win, and they no longer have a winning record, so you can't claim a win against a winning team). And, I think their are other factors (health at various times, margins of victory, etc.) to consider.