Now, regarding long term side effects, there are a lot of "alternative news" sources, and random internet anecdotes, which claim relatively common heart problems following vaccination, and some stories of healthy people dying a few days later, though these deaths can't be explicitly linked to a vaccine necessarily. These sources are not more trustworthy than the mainstream media, but if the 2020 election has shown anything, it's that the media is willing to die on the hill for their narrative. These alternative sources are the same sort that were correct about Russiagate and other such media nonsense. So I can trust neither side, and there is at least some fringe evidence that the vaccines are worse than we know.
About long term effects appearing, I can't know if this is possible, and I can't trust anyone who says they do know, since it has been so politicized. There are actually medical doctors who say it could be dangerous in this way, so again, I can't know whether they're crackpots or if a large number aren't just fearful for their jobs and such. If you were a researcher right now and you had some evidence to believe this vaccine could be dangerous long after the injection, I find it hard to believe you could get your message out to any credible mouthpieces at this point.
If, in a couple of years, everything is still fine, then I may relent and get the jab. But right now there is just no way to trust it without trusting institutions which have proven themselves liars.