He had no choice. It's a flimsy case that no one cares about. The Left have pursued it none the less, using biased rules unlike anything seen before.
We all remember that both the Clinton impeachment and the Nixon impeachment (for those old enough) were broadcast on TV.
So, it is a necessary part of the process, to try to make this look legitimate and comparable to the processes uses in those other cases.
Also: the Dems are very loyal to MS-NBC and CNN, those are major parts of the Democrat machine. They want this to boost ratings.
The Democrat machine is a major part of the MSM. The MSM is boss and all politicians know it. Just the public doesn't get it.
For example: The MSM could come out and bury Hillary Clinton or Adam Shifty within 24 hours.