Forum doesn't need money or traffic,
Are you certain about this? Wonder how did this forum survive without any traffic at all nor the money from advertisement?
Have a look here
https://bitcointalk.org/donate.html and then add up how much the forum has taken in donations.
I think those donation were made years ago and the last time it was update is back in april 2017, were bitcoin price was much lower compared to what it is now.
To sum it up hilariousetc answered the question.
Without any traffic at all this forum or any other would be dead and every forum or website needs money to run