Yeah, it takes a while for a meta game to solidified, so I can understand that with COVID messing with events.
About the tiers themselves, I fully agree with the Top Top and the Bottom Bottom.
The Top Tier has two characters with a ridiculously high skill ceiling, but also a lot of good tools even in the mid level competition. And Pyra/Mythra, well, they have great tools, and tons of them, they basically have two movesets, and unlike the other characters that are like that, both characters are actually High Tier by themselves, and they also have some other traits, but I'm not so familiar with them.
And the Bottom Tier has the two characters that need to be weak for the newbies' sake (also K. Rool applies to this design philosophy, but to a lesser extent because he's definitely better than this two).