Is Miami/Miami Beach a good place to socialize as a teenager?

Hi, I’m from Montreal, and my family & I want to go to South Beach from the 19th to the 26th. That being said, I have seen posts/comments on here talking about how right now is off-season or that the city is “losing its spark”. There’s also this assumption going around that Miami/Miami Beach is more of a 18+ or 21+ city and not the best for families. I believe the best way to make the most out of a trip is by making new friends and socializing. My question here is: Is Miami/Miami Beach a good place to socialize and make friends as a teenager, or would I be better off at an all-inclusive resort in the Caribbean?