Terry A. Davis popularised the term. He was a software engineer that ended up with a very bad case of schizophrenia. While unemployed due to his illness, he streamed while working on his own operating system that he built with the intention of “communicating with God”. While streaming, he used to go on these rants about how federal agents are spying on him, calling them “glowies” more often than not along the n word with a very hard r at the end. The term “glowies” has very racist associations.

In other words, you need to be somewhat fairly far down the alt-right pipeline if you actually talk about “glowies”.