Sure, here are some stats (last year) for two of the affected users:
User 1
- Posts created: 11,709
- Reactions given: 41,569
- Reactions received: 74,603
User 2
- Posts created: 5,959
- Reactions given: 37,974
- Reactions received: 38,875
Both users trigger the 502 error, suggesting the timeout threshold is hit even with the moderately lower (but still high) activity of User 2.