Yeah, an edge case. Because you've never experienced it, it didn't happen /s. As I said, all extremely common, at least in my experience. Getting sick on "farm backwash", usually by water bottle, happened semi-regularly. Sunscreen dripping into wounds from scraping veg and rocks along a mountain bike trail, that's a special hell that I'd be happy to describe to you. It's very real, especially if you're on a multi day trip without access to services. Which is a thing people do, btw.
Back to the OP, hairy legs makes things harder for long distance cycling. Especially multi-day cycling. The level at which this bothers you is a personal decision of course. I'm an average amateur mountain biker and I don't bother shaving. But I only ride 2 hours at a time! If I was going for longer trips ... yeah definitely, leg hair is a liability.