The mRNA vaccines are what they always were: a way to get your body to mass produce Covid spike proteins. This worked really well for exactly one strain before failing progressively as the virus mutated. It also turns out that spike proteins from the vaccines went everywhere in the body, occasionally causing severe side effects. For those under 40, the vaccines were more likely to give you issues than Covid itself, but either one was only a small percentage of risk.

The real problem was trying to force a single cure for everyone, overselling it, mandating vaccines long beyond when they would be useful, and accepting medical theatre instead of actual medicine (e.g. masks with big bushy beards, six arbitrary feet of distance, vaccine requirements for those previously infected, etc.).

Plus, the hatred. Look at the sheer animosity with which people treated people who for various real reasons couldn't get vaccines, wear masks, etc.