We can look at the list of Debian Developers and filter the list by "Current status".
There are 972 Debian Developers listed with the status "Debian Developer, uploading". These are people considered to be active.
When people resign/retire, their status is changed to "Emeritus". There are 449 Debian Developers with status Emeritus.
The status "Removed" is distinct from the status "Emeritus". There are 272 Debian Developers with status "Removed". This list includes people who have died, it includes victims who have been disappeared and it includes people who have failed to respond to any attempts to communicate. Some of these people may have been participating under a fake identity. Some of them may have become fed up with the politics and walked away without saying goodbye. Some of these 272 people that we can't account for may have joined the suicide cluster.
Public health statistics tell us that only one in four suicide victims leave a note. In a large enough group of people, for every one person who leaves notes like Frans Pop, it seems like a reasonable hypothesis that there are three more who we don't know about because they didn't leave a note. Ian Murdock left notes on social media. Richard Rothwell left notes.
With or without a note, in this list of 272 people "Removed", there will be many more we don't know about because their families would never think to tell us.
How many of these 272 vanished after some secret humiliation on the debian-private mailing list?
How many bloggers have committed suicide after WIPO denounced them with accusations of bad faith?