The title of the user page https://tyv.wikipedia.org/wiki/User:Kaganer appears as "Участник:Kaganer", where "Участник" is a namespace name in Russian.
The title of the user page https://tyv.wikipedia.org/wiki/User:Agilight appears as "Aжыглакчы:Agilight", where "Aжыглакчы" is a namespace name in Tuvan.
I'd expect both of them to appear with "Aжыглакчы".
Perhaps it has something to do with gender aliases and Russian fallback:
- If I set my gender in the preferences to "they" and make a null edit on my user page, it appears in Tuvan, "Aжыглакчы".
- If I set it to "he" and make a null edit, it appears with the Russian masculine namespace name "Участник".
- If I set it to "she" and make a null edit, it appears with the Russian feminine namespace name "Участница".
Gender aliases are irrelevant for Tuvan, and I'd expect it to appear as "Aжыглакчы" in all cases.