That’s what euphemisms are for-- making a negative sound positive.
I’m half-joking here, but only half. I once was in a predominantly Asian neighborhood (in Silicon Valley) with one the Mexican guys I work with. He commented about how quiet the neighborhood was and how much noisier it would be if Mexicans lived there. It was funny, and probably true!
In my experience “vibrant” is often applied to the local gay community.
So John’s right, you’re saying.
I’ve lived in places that are 90%+ Hispanic, and mostly Mexican-American, and while I wouldn’t say they are “vibrant,” there is some real diversity. Not all Mexican Americans speak Spanish at all, other speak nothing but Spanish, and there is also a tremendous amount of income and class diversity. There are also real racial divisions within the community, despite the presumption that there is a uniform “brown” identity. The (almost all Latino) folks at the golf course or in the Starbucks are clearly not the same crowd as the (almost all Latino) folks at the flea market or lowrider show. There are also subgroups such as indigenous people from Oaxaca or the Yucatán, Chinese-Mexicans, Lebanese Mexicans, and other ethnic minorities with a minority.