RAW Underground has been nixed by WWE and it might not return anytime soon. They seem to have a legitimate reason nixing the segment and it had to do with the COVID-19 pandemic.
On Wrestling Observer Live, Bryan Alvarez talked about the current situation. He revealed WWE nixed the segment owing to the recent COVID-19 outbreak. The reason there is no longer any RAW Underground segment is due to the segment incorporating talents from RAW, Smackdown, NXT and the Performance Center. The company does not want to do anything that involved the mixing of brands.
There is concern that if a segment of Underground is held and there is another outbreak in WWE, then Underground has the potential of spreading the virus to every brand that is involved in the segment.