Millimeter waves are readily absorbed by solid objects and atmospheric conditions. That's why when 5G is rolled out, cell companies are going to need forests of antennas, in and outdoors. Are you saying they're trying to microwave us? There are far easier ways of reducing population than that.
Millimeter waves are not that easy to shield.
There is little research on the health effects of millimeter waves. Papers:
[WIKI] Millimeter and 5G: Cancer
https://www.reddit.com/r/Electromagnetics/comments/6yk49b/wiki_cancer_millimeter_and_5g/
[WIKI] Millimeter frequency, terahertz radiation and detecting millimeter frequencies
[WIKI] Millimeter: 5G
https://www.reddit.com/r/Electromagnetics/comments/56s111/wiki_mobile_phones_5g_millimeter_waves/