Players are from everywhere. Many have played in cold.
The franchise has been around since 1966, with Buffalo, Boston/New England, and New York always there each season.
Every other team in the NFL (save dome teams) plays in cool to cold temperatures at some point. Even the I-10 corridor teams play in cool weather at times. The rest of the U.S. is not Florida. (Heck, Pensacola has had snow two winters in a row, 8 – 10 inches in ‘25! We all survived it. High school teams play in the 40’s here in late autumn, so if they can do it…)
If anything, it’s warmer than it used to be, not colder.
Acclimatizing is fine for the team. It’s different to be outdoors in, but the ball is equally cold for both teams. Same field, same wind chill. It’s 4 parts mind game and 1 part infrequent conditions of play.
It’s time to overcome the cold weather gremlins. If they don’t, the only path to a Suoer Bowl for Miami will always be the number one playoff seed.