Meh, I think Johnny should be seen separate from the dissappointing endings.
I love to hate him. He is such an asshole and I hate what he is doing to V, but that actually is good writing imo.
Pretty similar to why I like Joffrey, Moff Gideon or Ramsey Bolton.
It's not that I hate him for being bad, I love Handsome Jack in Borderlands. He's mean, petty, childish he's everything hateful but he's amazing at it. You have to hate him, he's irredeemable.
Johnny is a spoiled fucking brat I want to slap and scream GROW THE FUCK UP. That's not good writing lol