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In level 100 formats, the indicator for a Pokemon's level is hidden if that Pokemon is level 100, as 100 is considered the default. Shouldn't the same happen in tiers where a lower level is the default?
As a VGC player, I definitely prefer having the levels visible. In fact, as a randbats player as well, I would rather have level 100 be visible as well.
Not sure I can speak for anyone else, but when I don't see a level indicator I instinctively think level 100 - and I've only been playing for a handful of months. Perhaps it could be a toggle-able setting in the menu?