At the same time though, a bunch of people who know each other and the people allegedly involved could very easily share the same incorrect testimony. You wouldn't believe in bigfoot if 5 guys drinking beers swore they saw him while they were camping. Sending someone to prison or worse is much higher stakes. DNA evidence might be too extreme, but I'd expect some sort of evidence to back up a testimony. "What if the witness was wrong" just seems like always a reasonable doubt, or at least the number of witnesses who would need to corroborate something such that it ceases to be a reasonable doubt is impractically high.

It's a nitpick, but testimony under oath is evidence to US courts. All evidence is either testimonial or circumstantial.

Damn its almost as if juries exist to act as the sovereign so the violence which sustains the law can be vested in a general public that cannot be held accountable as a whole, similarly to how at least one member of a firing squad always has a blank.