Here is an example from Twitter :
Someone said Josh Hawley had the charisma of a Moai statue and someone else replied: Harsh on Moai
A type of joke you hear a million times but I admit it made me chuckle.
The basic template: insult X by comparing it with Y and the punchline is that the real insult is to Y.
Is there a name for this type of joke? When was it first used? What are famous examples or just ones you like?
TV Tropes calls it Insult to Rocks.
I don’t get it. 
Not really a joke …
Sardonic ?
(a “sardonicism” ?)
What part of it don’t you get?
A Moai statue is one of those Easter Island statues that are completely expressionless and vacant. The insult is saying that Hawley is even more stone-faced than that.
Ah thanks. TV Tropes is such a treasure; it nicely lists the different variants too. Doesn’t say where the trope originated though this one may be an early version:
I know about the statues, but how is “Harsh on Moai” anything other than a random collection of words?
It was harsh on the Moai statues to be compared to Josh Hawley.
Oh.
Har-har-har-dee-har-har! 
Seems to me like “[That is] harsh on [the] Moai” is a pretty evident reading of those words.
Not to me it doesn’t.
Ernest Hemingway never gets it.
“Harsh On” is just some hipster phrase my teenage daughter might use in a text message.
The joke type is more common as: “He has the face of a wildebeast.” Response- “Hey now, there’s no reason to be insulting wildebeasts like that.”
I would call it a form of misdirection. The humor relies on the element of surprise. As such, you see it go from edgy to mainstream and in so doing, losing much of its potency when you can see it coming.
That’s an insult to getting it. Amidoinitrite?
Yes…
This information would have been more useful to me four hours ago.
Dunno.
And there’s an even earlier example under “Theatre”:
In Titus Andronicus, Lavinia likens Tamora to the legendary queen Semiramis, who founded the infamously sinful city of Babylon and was associated with the lascivious goddess Ishtar of Mesopotamian mythology. Then Lavinia backtracks on this comparison, not considering it fair to Semiramis:
Ay, come, Semiramis — nay, barbarous Tamora,
For no name fits thy nature but thy own.
harsh (adj.) Meaning “offensive to feelings” is from 1570s; that of “disagreeable, rude” from 1610s.
