Fulton County regularly allows cameras into the courtroom, and sometimes they run it on YouTube, It's from their public access tv channel and it's how we watched the Stop Cop City council meeting, so it's not just because it's the Donald circus. Fulton county is pretty open with court cases.
As for why it should be televised, we deserve to see the evidence and have the whole picture laid out, you deserve to hear what the Government's case is against him and if it helps even 10 percent of his followers to see the light, that's a plus.