I mean, it's not a great idea. I'm young, healthy, vaccinated, masked, and still got it recently. And got pretty sick, too. It's out of control in the whole state right now. If I didn't live here I would stay as far away from FL as possible. It's not just that the cases are so high, it's that so many people still don't care AT ALL. They still aren't wearing masks, they still aren't distancing, etc. I can basically guarantee you will have no personal space bubble and unmasked people will be swarming you.
Just because someone else may have come down here and not gotten sick (or more likely not KNOWN they did) has no bearing whatsoever on what your outcome would be. You say your immune system is already weak but aren't willing to do anything to try to boost it. What about the other unvaccinated person in your party? Do they have a good immune system? Do they mask and distance and sanitize and stay in their bubble at home? What if they bring it back to someone they love or work with, etc? What if that person gets it? Even if you, by some miracle, don't get sick...is someone else dying worth you saving money? You aren't risking only your health. You're risking the health of everyone you come in contact with for at least 2 weeks, everyone your traveling party comes in contact with, etc.
It's a bad idea to travel at all right now. Even worse on a plane. And even worse to a state that's a hotbed for both covid spread & anti-mask/anti-vaccine people. I think what you were really looking for is people to say "oh just take your trip! this whole thing is so overblown and silly!" but that's just not reality.