There's a pretty big spectrum between "safe" and "catastrophic".

Probably only a fraction of a percent of the transmission energy is getting absorbed by the body, but that doesn't mean I'd want to try it out.

I think the idea is that you'd take basic measures to try to avoid/discourage exposure, but you wouldn't have to worry about any extreme safety measures to guarantee it.

The beam is likely much wider than a person and at a precise frequency requiring a tuned antenna to convert it efficiently to electricity or heat. You might not want to stand in it for minutes, but passing through would be safe enough.

Theoretically, it should be equivalent to standing directly in front of a space heater in the worst case (if the human absorbs 100% of the microwaves).

Well, apparently. For reference neutrinos from the Sun are around 30W 24/7 and does it harm us?

https://www.quora.com/How-much-energy-is-in-the-neutrinos-pa...

Yeah but microwaves aren't exactly neutrinos, those don't really interact with much of anything at all. Like comparing a sound wave with a dump truck hitting you in the face. Water absorbs microwaves like a dry sponge, which is why microwave ovens are a thing and wifi over water sucks.

Humans are what, 60% water?

Depends on how focused the energy is. The sun is beaming over 1MW per square meter and it doesn’t vaporize people.

Actually one kilowatt per square meter.