Last year that number was ~2.6 million and year before that ~2.9 million that just confirms something we are all aware, that forum activity has been on the decline for years and with the mixer campaign ban I expect numbers to go down even more.
There's a general downtrend, but it's not like the decline in activity was constant year-on-year, i.e. 2022 was slightly better than 2020. But yeah, dropping below 2 million would be the worst result since 2012, so it's getting slightly concerning. But maybe it's just a natural cycle, Bitcoin is no longer a novelty and there are now plenty of other places it can be discussed, so bitcointalk is no longer the first place to go with any btc-related questions.