According to Urban Dictionary, "gagged" means "to be amazed or stunned by someone or a situation of some kind." The site says the term is also "often used within the LGBT community and the ballroom ...

I’m not the least bit fond of internet slang, which probably means that I’m the worst possible candidate to endure the likes of Needy Streamer Overload: Typing of the Net. Perhaps I’m getting on a bit ...