Though the hearings apparently weren't broadcast on cable Fox News, in my metropolitan area (which is very liberal) they were broadcast over the air on the local TV Fox News station (along with ABC, CBS, NBC, and PBS).
Hundreds (not simply a few, not simply 3 to 7) of rioters stormed into the Capitol building and seriously injured some police officers and killed at least one of them. However, I didn't see any of the rioters using guns or carrying guns, though some had other weapons (that is, objects they used as weapons) with them. Trump made some comments (including saying to be "wild") which motivated/encouraged many of the rioters (and which caused millions of people to falsely think the U.S. presidential election was stolen from Trump), but none of Trump's words explicitly said to be violent at the U.S. Capitol building.
Other than having a political purpose, I can't think of any reason why congress is doing its investigation and hearings, since the U.S. Department of Justice (DOJ) is doing their own investigation, arrests, and prosecution of individual people involved.