Judging from the graph view (https://freenginx.org/hg/nginx/graph https://freenginx.org/hg/nginx/graph), it has to do with the QUIC branch landing onto the main

Judging from the graph view (https://freenginx.org/hg/nginx/graph https://freenginx.org/hg/nginx/graph), it has to do with the QUIC branch landing onto the main branch, suggesting he had little role in the QUIC development but heavy role outside of it.