Let's say you divide up all statements made my humans into categories based on whether they're funny or not funny, and based on whether they're line-crossing or not line-crossing. This gets you four categories of statements:

A) Not line-crossing, Funny: This is a regular joke.

B) Line-crossing, Funny: This is a joke. Some people may not like the joke depending on how you're crossing lines, but you'll basically have people with you.

C) Not line-crossing, Not Funny: This is just a non-joke statement. If you were trying to make a joke, at worst you're a hack or a weirdo.

D) Line-crossing, Not Funny: You're an ass. You'll get some people tripping over themselves to prove that they're hip in their defense of your "joke", but you'll also lose a lot of people.

The problem you get is that no comedian bats a thousand, meaning that comedians shooting for B end up in D a lot, and I'd classify pretty much every tweet that's getting buzzed about as a member of that group. That's not an indictment of Noah's overall career in comedy. Nobody bats a thousand, and I'm sure that Noah knows that when you try to make a joke at the expense of fat women, for example, if your joke sucks (and Noah's do, because like every other human on earth, sometimes he makes jokes that suck), then you're not just a hack, you're an ass. Every comedian shooting for D is going to look like an ass sometimes. If we want B-Type comedy to exist, comedians are going to end up making D-Type statements.

It's a basic rule of (good) comedy that if your joke is uncomfortable, it needs to be funnier than it would be otherwise. (Unless you're a comic that's riding hacky jokes on raw shock value and actually aiming for the ass audience, which I think it's pretty clear is not the case with Noah.)

That said "I was trying for B" doesn't mean that you're not an ass when you hit D. You said an ass thing, and you deal with the consequences of having said an ass thing like an adult.