Why do both Scotts and Eliezers pseudonyms end with 'ain'? Yvain and Iarwain.

Edit: and small frustration what is up with the lack of timestamps? I know the internet is getting worse and worse with those replacing the 'posted at 22 feb 2022' with 'posted 1 year ago' things (as predicted in the transmetropolitan), or just having sites autoupdate the timestamps to seem current for the google ranking (saw a '2024' guide which in the text still talked about 2023 and had a mid 2023 timestamp, so somebody messed up a script there). But no timestamps at all is a bit odd, the only timestamp I saw was 'Jan 19, 2024, 3:29 PM' and that looks suspiciously like 'now'.