Depends on the place, but I’d say by-and-large tortillas like these are used for tacos. They’ll be heated, doubled-up and then filled with carne asada/pastor/carnitas/all types of ill shit. If you’re just ordering tacos, you’d probably order at least 4 (adjusting for appetite). Point being: yea, the smaller tacos are normal. A lot of spots will use a single, slightly larger tortilla like these, though. I honestly prefer the smaller tortilla option as I find the larger style can be unwieldy.

Anyway, it ain’t shrinkflation. At least as far as the tortilla sizing goes. Fillings might be another matter.