I'm not against this stuff per say.
There's just a frame of mind involved with this stuff that's interesting, and it's a reflection of modern day access as much as bodybuilding.
There's no evidence of loading up on any vitamins, minerals, or "immune" enhancing compounds that will help you fight against COVID transmission. Being healthy, having good blood pressure, not having excess bodyfat, low systemic inflammation, hydrated, and well slept will do more than slamming another pill or injecting B vitamins. People sleep 5 hours a night, and talk about what megadosing vitamin C is going to do for the immune system.
It's the same as the person taking 57 different health supplements, and looking to add more to their regime. If something helps help you push towards the direction of health that's good, but the kitchen sink approach doesn't do anything in the long term I think.
People also extract large conclusions from small disjointed studies. Just my opinion on this.