I am sure that more than 50% (maybe the percentage is even more dramatic) of the activity on the forum is due to paid signatures. even in spite of that, some DT members or those who had almost secured a place in a better-paid campaign have left the forum. just to imagine how different it would be without stimulation through signature campaigns.
I think its probably closer to 90% just going by how many posts have paid signatures underneath them. In theory sig campaigns should just be a bonus to people who were already posting anyway, and I think for some posters this holds true. However, its pretty clear the vast majority are here just for the payday. This has led to an ingrained culture of shitposting-for-cash where genuine contribution is quickly buried beneath a flurry of dull, meaningless drivel. Most visitors who aren't already a member here aren't gonna wade through it to find the rare, interesting nuggets of information... they've effectively stopped coming here.
Similarweb Global Rank for Bitcointalk (taken from what is
currently available and
archived)
Sept 2022 - 35,390
Apr 2022 - 33,489
Jul 2020 - 24,833
Jul 2019 - 7,717
Jul 2018 - 2,671
Aug 2017 - 1,890
Feb 2016 - 7,762
Nov 2013 - 33,073
At the same time, there is no motivation to attract more traffic. As theymos recently explained, the forum is doing quite well financially. Bitcointalk really just has one purpose now and theymos has one job, and that is to make sure satoshi's posts remain accessible and in tact.