This question got an off-topic slap on the Sci-Fi Stack because I asked about real-world physics, rather than fictional physics. I want to completely disregard the canon. Hypothetically put this into a real-world scenario where someone has somehow fit a power source with the output levels of a nuclear reactor (not a nuclear reactor, just something as strong, but small enough to fit into this scenario) into a hilt and made a lightsaber that looks like one in the movies but functions as a real-world object.
Lightsabers are (seemingly) closely related to plasma, which would be the closest tangible thing to a lightsaber in the modern world. Given the fact that a lightsaber would be a constricted plasma arc, it could reach temperatures of up to 25000°C. Wouldn't a lightsaber end up burning a person based on the heat it gives off?
What about general lightsaber wielding and the light plasma gives off? Plasma cutters reach up to 800 Amperes, and that's a smaller sort of plasma arc. You need specific eyewear for these plasma cutters because it can cause eye damage relatively quickly, right? Lightsabers are three feet of constricted plasma. Wouldn't this have a blinding effect after time if eyewear wasn't worn?