It changes over time and by area.
Where I live, pit bulls have been big 10 or 15 years I know that is not one specific thing, you know what I mean).
Pugs are very popular right now.
Yorkies and little poodles are always common in high-rise neighborhoods.
Before pit bulls,the popular “macho” dog was the rottwieiler. I haven’t seen one for a few years.
Chihuahuas were big just a few years ago, I think pugs took that niche.