Your assertion is right: activity seems to have decreased on FSE, slowly but steadily. As an example, last August was the quietest month in terms of asked questions since March 2015, and the second quietest month in terms of responses (the first being May 2020) since October 2014.
How can we explain it?
It is a subject I've been thinking about for quite some time. I tried to analyze some data, and here are my leads so far:
- Due to the "StackExchange vs community" situation, we lost a lot of core members.
Several valuable contributors (and even moderators) decided to dramatically decrease (if not totally stop) their activity on the StackExchange network, following what happened with Monica Cellio about a year ago. Two of our moderators (Gilles and Stephane) resigned from FSE. By looking at our all time best contributors, only 4 out of the top 10 remain regularly active to this day. Out of these 10 people, at least 4 of them directly expressed their disagreement towards SE policy.
Another stat: so far this year, 4 people earned 1,000 reputation or more. Last year, there were 21 people in that case (to make this calculation, I took people who got 1,333+ reputation over the year because we are currently at ~75% of the year, and I had to assume that their progression was linear).
- We fail to attract and keep new valuable contributors
By looking at this year's best contributors, only 3 out of the top 20 joined FSE this year, and only 1 of them has been active in the last month.
Using StackExchange API, I also looked into the number of new users, and it has decreased this year (for this year, I calculated the expected number given the current number at the current time):
| Year | User total | Diff. (%) |
| 2015 | 2245 | - |
| 2016 | 2830 | +20.7% |
| 2017 | 3240 | +12.7% |
| 2018 | 2742 | -15.4% |
| 2019 | 2750 | -0.3% |
| 2020 | 2580 | -6.2% |
What can we do?
- Be more welcoming
I think this is a problem common to all sites on SE network (probably because of the system itself), but I'm convinced there are a few simple things that we can do to try and keep our new users.
-> Be nice: try to greet people, make them feel welcomed, and explain them why they did something wrong.
-> But also to each other: try to avoid arguing (I've seen a few comment battles recently, and honestly some of them could have been avoided).
-> Reward: upvote new users when they make relevant contributions. If you downvote, explain!
- Try to bring our core members back
To be honest, I don't think there is anything we can do at FSE. But I have hopes that StackExchange, as a company, is trying to build back the link with its community. There seems to be a real inside questioning, and maybe that can help some of our good old members to come back and try to help us build FSE back.
- Encourage interactions and content
As moderators, I feel like there are a few things we could do to improve the situation, and Tsundoku always has nice suggestions based on what happens on other SE websites.
First of all, he suggested that we encourage voting, like they did in Latin and LLSE. The reasoning is that, if we tell people to vote, they will look at more questions, more carefully, and might want to bring their own grain of salt by attempting to answer. Also, having more vote interactions is sane for the site because it generates more reputation, and encourages good contributors. Not everyone is driven by Internet points, but let's face it, a lot of us are.
Another suggestion I could make is that we, as moderators, animate the community. For example, we could have a monthly theme, a bit like Literature SE's topic challenge, where we reward all questions and answers with bounties. The topics could be French authors, writing styles, curiosities of the French language... The general idea is to encourage our already active users to post more content, so that the site gets more dynamic.
To be honest, I'm not sure that there is much more we can do at our small scale, apart from advertising FSE everywhere on the Internet. But maybe with more interactions occurring on our site, things can start going upwards again!