From a linked article [0] there's a screenshot of Bram's github activity and this text:
> Sad
> Perhaps all these things add up to why it hit me when I read the news that Bram had passed away. In the message, his family made it clear that Bram was ill (‘a medical condition that progressed quickly over the last few weeks‘). This was unknown to most people and made the news all the more surprising.
> And it made me even sadder when someone pointed out Bram’s recent GitHub activity.
[0] https://j11g.com/2023/08/07/the-legacy-of-bram-moolenaar/
EDIT: From BDFL list in Wikipedia Bram seems to be the first to be marked as †.