So on a weaker FDA it would be exactly the same, except that now your guarantees about the safety and efficacy of the drug are reduced. How is that better?
How about a weaker FDA that simply advised people on the safety and efficacy of drugs rather than forcing everyone to follow their rules? That would technically be a weaker FDA, but enable more freedom for patients and their doctors to pursue treatments that they found efficacious.
How about a weaker FDA that allowed the import of drugs from other countries? That would create international scale competition for the US drug purchasing market.
There are lots of ways that we could get creative in solving these problems if there weren't a monolithic government agency in the way of our personal freedoms.
Because when people are fucking dying they tend to try whatever options they have left even if they're not guaranteed to work 100%. So now the market every disease for anyone in a precarious position will be saturated by shitty chemicals tested with far less rigor.
Seriously, it's like you're just ignoring what happens in every country that currently does have weaker systems and who look up to the strong regulatory practices of the US and Europe for exactly that reason.