Because out of the tens of thousands of "experts" in-favor of the vaccines, YOU choose to listen to the hundred or so that disagree due to philosophical, not FACTUAL or scientific, reasoning.
And that's the problem. When you have to cherry-pick information to prove your point, that should be a clear indicator that you're on the wrong side. But people are arrogant and can't let their pride take a hit, so they refuse to acknowledge that their perspective might be flawed.
There's a reason why "peer-reviewed" papers are a thing. You can't just put down bullshyt and it'll be accepted by the scientific community, because that would be extremely counterproductive and would take people longer to reach breakthroughs because they'd have to go and validate said research for themselves before continuing. They come to a conclusion as a collective because the results can be verified again and again while remaining consistent with previously existing data. And health professionals from all across the world are working together, which is why progress is moving a lot faster.
But no, people read reddit posts and watch five hours of fringe YouTube videos, and suddenly they know more than the people that spent a ton of money and a chunk of their lives studying this through esteemed educational institutions. Even
if their independent medical research and studying involved valid sources, there's a reason when it comes to any major career, you have to do a practicum for a few weeks. Knowing theory is one thing, putting that into practice is a completely different story. It's no different than reading the Driver's Handbook, never getting any in-car driving experience, and then thinking you're going to pass your road test with flying colors. You either know it or you don't.
These people don't care about the truth. They just want to be right, even if it comes at the cost of other people's lives.