Nah, he was a great character.
His arc wasn't just about him being a crackhead.
There are layers to his character, I guess it just depends on how the viewer chooses to see him. Season 4 was the most depressing when it came to his development, where he finally hit rock bottom, but in the worst way possible after promising himself he wouldn't fall that hard.
Not to be a snob, but OP is probably the type to not really understand the whole basis of The Wire and its array of characters, skipping seasons and shyt; just watching it for the action, and there's nothing wrong with that...
However, I know it's been said before, but to watch The Wire, you gotta really pay attention to every detail and connect the dots; it's not like your average show based on crime, police, etc, where the writers make it easy for you to understand without thinking too hard, The Wire is different in that regard, it's supposed to be thought-provoking when it comes to highlighting societal issues and how it affects the people within it and their motives for why they do the things they do which were forced upon due to these issues

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