Someone should strike down the US Senate because of malapportionment.
I could theoretically see a SCOTUS with like 7 liberal appointees ruling that Senate apportionment without respect to state population violates the 14th and 15th Amendments. The remedy would probably be to give the large states a bunch of extra Senators, not to abolish the chamber entirely.
Except the Constitution explicitly says that not only is the Senate defined as representing each state equally, it's (according to dominant interpretation) impossible to change that even through amendment without the consent of every state involved. It's the one single solitary entrenched clause in the Constitution, and the Constitution can't be held in violation of itself.
You're right.
Incidentally, here's something I've always wondered. So article V says that certain things in the Constitution can never be modified through Amendment. But if you really wanted to modify them, wouldn't it be very simple to circumvent that clause? You simply need to pass two Amendments instead of one: the first Amendment repealing the clause that makes it impossible to change what you want to change - then the second Amendment could enact all the changes you want. Is that correct? There is nothing in the "thiscan'tbechanged" clause that says the clause itself can't be changed.