Time for the realest of real talk I'll give as far as bills go since this is free speech zone. I'm sorry if someone takes something personally ;_;. I'm only trying to state what I think
Bill: Bane is super top tier
I think 16bit upplays Bane and with his influence in this community it's caused everyone else to start upplaying him. I think he upplays him mainly because he has the perspective of one character that gets bodied by him, so he sees him in the tier list as more dominant than he is. I had the same mentality with Sinestro for a while, but then I started thinking about him more from the perspective of those who have good options against him and started changing my mind.
Myth: Shazam is a bottom tier yolo character
I think Wonderchef has the best understanding of Shazam and the other top players of him don't have the right mindset/playstyle required to play him.
Myth: Nightwing is good
I think Nightwing is a good character with all the right tools that aren't adjusted right for this game. Nothing fast enough that rewards enough, nothing to give him mobility without a lot of weaknesses, nothing strong enough to control airspace, weak against interactables, nothing great to push him over the edge like a strong trait or a useful super. He just feels super mediocre. A good player could still do decently with him, but your strong point being good footsies doesn't mean much compared to what characters like Sinestro, Aquaman, Bane, or even Catwoman can do with them, especially considering how little some characters care about having good range.
Bill: Multihitting things make Lex's trait useless
This is super annoying. Having quick, multihitting moves means it can sometimes be more difficult to get my trait out, but using it is the same as playing a regular neutral game with the bonus that you can take an armor hit whenever you want. This more means I know people are going to try certain moves more, which I can still blow up.
Bill: Black Adam is still top 10
Black Adam went from a strong spacing/keepaway character to a character that just has decent footsies. He has some good corner stuff, but I haven't heard any good arguments for why he's more than upper-mid tier.
Bill: Zatanna is a super complex character that takes a literal genius to win with
I think Zatanna is definitely one of the more complex characters in the game. That being said, I think it more takes a right mindset and playstyle than a master of fundamentals and tech to do well with. She still has room for improvement for sure, and I doubt everything good about her has been found, but I don't think just her having an unorthodox playstyle and a lot of special moves makes her that much higher than the rest. I don't think people should be so intimidated to pick her up.
Myth: Joker never stood a chance
I think Joker's metagame and execution requirements make him a way more complex character than he's usually made out to be. I don't think all the right people are playing him, and the ones that are haven't developed him to what his potential might be.
Myth: Grundy is bad
I think a lot of Grundy players gave up on the character too soon because of throw invincibility. There's a lot more to the character than getting free walking corpses, imo. Tyrant still doing well despite not really focusing much on the game anymore shows that the character can still do well. And I know there's others who have developed some stuff that might make people eventually have a better opinion of him when combined with a solid use of his metagame.