GD and P&E do have some criteria but no hard rules.
If the thread is new and is offering nothing new, we’ll close it. That is stated in the GD rules.
If the thread has been around for awhile (usually months) and it is down to a few principles yelling at each other and generating flags; we’ll probably close it.
Please take a look at the GD and P&E rules:
This will give you a feel for what guides us to some degree.
There is a thread right now that just started I need to review for possible closure. I need to ensure it is covering new ground.