I know this is probably an unpopular opinion, but I believe a restriction is needed for changing your username within Gwent, not necessarily for the whole GOG account.
A few months ago a post was made about the impact changing names might have in the “seriousness” of the competitive scene. My point goes towards avoiding what we’ve been seeing these past months in two cases:
The “memers” going for the “NoGGfor________”, including “NoGGtoTLGTrash”, “NoGG4Milva” and other multiple examples.
The result of the whole situation with WangID2021, including multiple variations of “TLG_WangID2021”.
(Examples are taken from the current top 100 players on Pro Rank, by the way)
What happens if one of these “funny” names qualifies for a tournament?
Source: https://www.reddit.com/r/gwent/comments/rdi4os/about_changing_usernames/