And why should it? According to Google Trends, forum activity in 2015 and 2016 is roughly equal to activity right now. And that was way before there was a merit system. The interest is measured in percentage so we're at 5% of popularity the forum had in 2018.

As long as google search queries about bitcoin related things turn up with bitcointalk links in the first page of results, I don't see a problem with the way things are going now.