Going off of MascotDB.com
, the top 10 most popular sports team nicknames in the US as of 2023 are:
- Eagles
- Tigers
- Panthers
- Bulldogs
- Warriors
- Wildcats
- Lions
- Cougars
- Knights
- Mustangs
So why is the trope named after the 6th-highest ranked team instead of one of the others?
To start, the Eagles, Tigers, Panthers, Warriors, and Lions already have teams in North America's three biggest professional sports leagues (the National Football League, the National Basketball Association, and Major League Baseball) and accompanying pre-existing large fanbases, popular image of that team and fanbase which might bleed into the fictional team whether the author wanted to or not, and heavy financial resources of those leagues to make using those names at minimum tricky in works of fiction. The Philadelphia Eagles' fanbase, for example, has a pervasive reputation of being, depending on who you talk to, either very passionate or very crazy and insane. The Tigers (last World Series victory 1984) and Lions (last NFL championship 1957) are both from Detroit, which combined with the city's reputation as a Dying Town (from its peak in 1950 the city has lost about 2/3 of its population as of the 2020 US Census) risks giving a fictional Tigers/Lions team an aura of being a Butt-Monkey.
In addition to the previous, "Warriors" also has the possible added baggage of having been used as a replacement name for a previous one that was eventually changed for being racially insensitive (at best) for actual Native American people groups — this isn't the case for the NBA's Golden State Warriors, but it's not too uncommon a situation for various US high schools as the Values Dissonance of those kind of names only grows.
The Bulldogs don't have a major pro team named for them, but do have a few collegiate programs named after them; the catch here is that one of those is the University of Georgia, who have such an outsized standing and presence in college football (the college sport with by far the most visibility in the US sports landscape) that they may as well be pro-level in terms of recognition and the layman sports fan will tend to default to thinking of them rather than, say, Gonzaga University or Butler University (who have more standing in college basketball, the college sport with the second-highest fanbase in the US — Gonzaga has had no football program since 1941 and Butler's has never played in the top-level NCAA Division I FBS).
Cougars has a couple of roughly equally prominent college programs with that name (Washington State University and Brigham Young University), but has the unfortunate coincidence of also being a slang term for Mrs. Robinson and so are ripe for jokes that at minimum can distract the reader from the intended story, which most of the time probably doesn't involve such risque content.
Mustangs suffers from the same issue as Bulldogs in that there is only one major college athletics programs in the US that uses that nickname (Southern Methodist University). Further compounding it is that that university's football program has been historically tarred with a major pay-for-play scandal in the 1980's that resulted in the only time the NCAA has ever instituted the proverbial "death penalty" on a school's football program. Even beyond the historical baggage, mustangs are really only found in the Great Plains areas west of the Mississippi River and east of the Rocky Mountains — being geographically restrictive in where one can find these animals makes its applicability as a generic nickname for Everytown, America limited at best.
Knights is probably the only other nickname on this that doesn't have the clear potential pitfalls of the other names, and even then it's still a bit iffy with regards to possible historical baggage (popular culture image of them, the Crusades, and being associated with European history specifically), possible association with Batman's nickname of "The Dark Knight", and, going forward, pro-team use with the NHL's Vegas Golden Knights (who started play in 2017 and immediately made a name for themselves by advancing all the way to the Stanley Cup Final in their first year).
Going farther down the list (#'s 11-20) yields a bunch of less common nicknames that are still already in use by pro teams (e.g., Falcons, Cardinals), already associated with a big-time college football program (e.g., Trojansnote , Spartans), are potentially racially insensitive (Indians), or some combination of these. Going any further and the names stop being useful as a generic nickname for a given fictional high school.
Thus, we end up with Wildcats as the go-to generic team nickname in fiction as the highest-ranked nickname without obvious pitfalls. Yes, as mentioned on the main page several university athletics programs use Wildcats, but none of them have been the go-to university program the ordinary real life sports fan will think of when the name "Wildcats" is mentioned — Arizona, Davidson, Kansas State, Kentucky, and Villanova all have had success in college basketball so none of them consistently dominate the sports talk circuits there year-in year-out (at least not to the point of Georgia in college football), and none have had sustained success in college football (if they even have a football program at the top-level NCAA Division I FBS).
