Guess the title says it, can we have a true talk without it for the sake of it about Bitcoin? Not like you're paid to say something.
Sure. we can do that.
There is board in forum called
Serious discussion that doesn't allow signature advertisement, and for even more serious discussion without any kind of advertising or junk posts there is
Ivory Tower sub-board.
You can also have a discussion in Off-topic section, but there are other type of problems in that board.
Third option you have is to create self-moderated topic, you are moderator and you can allow only discussion without advertisement, deleting anything you consider spam.