For the NHL I've only been collecting since 2017 officially so only one team, the New York Rangers have crossed the 1000 card threshold.
In NASCAR Hendrick Motorsports leads the way with 4277 cars recognized by the Database, but I'm sure it's many more in reality.
For the NBA, which makes up roughly half of my collection, the Chicago Bulls leads the way with the Database says 4495 cards, although it's actually less than that since college cards, checklists, multi subject etc. are included when they should not count. They have about 400 cards more than the Lakers, and that's about how many cards of Jordan upper deck shoved down our throats after he retired the second and third times.
I'm not a team collector. This is just what I've collected being a set collector for the past 30+ years.
VERY slow trading due to health problems. Not transferrable so safe to trade with, just moving is painful and can't always access the cards.
Cardboard History My COMC
New Collection Website: Cardboard History Gallery (Still under construction)
Tips on how to make your scans look like the card does in hand (No more washed out, fuzzy scans!):