This could be related to Show default value for drop down on tenant variables (#2582), but I’ve noticed that when I have a dropdown project variable that has a default value (similar to the one shown in the image on the above issue), when you go to view the variable on the tenant it always displays the default value, to the detriment of the dropdown.
This default value display persists regardless of which value you select from the dropdown.
I would expect the dropdown option with the default value to be selected if (and only if) there was no overriding value already saved with the tenant.
I’ve seen this in both v3.4.4 and v3.4.5.