You must repeat the 7th Grade

Constitution never says how the state is supposed to distribute its electoral votes.

Never.

It's winner take all de facto - that's just what the states decided to do. The Constitution NEVER mandated the winner-take-all rule.

They will have a hard time arguing that the assignment of electors depends on "outside forces" (the national popular vote) and disenfranchises the states voters (if result is opposite of the state's popular vote wishes)

The Constitution very clearly left it up to the states to assign their own rules on how the Electoral Votes will be distributed. That's basically where the entire problem comes from - over time, the states locked each other into a gamesmanship state of trying to maximise your influence over the election process.

The Supreme Court does weird things but if an alliance of states want to trigger a popular vote distribution, then the Supreme Court has to allow it because the Constitution expressly says that the states can do it however they want to.

But that's my point, the Supreme Court does not have to allow it - it is not absolute. It will be challenged, and like other constitutional issues - free speech, gun rights, etc. - the state laws will have to argue MORE than just "we can do whatever we want."

For example, the state cannot say "African american votes won't count toward the totals used to assign electors."

They have to argue both sides of the "popular vote" argument (i.e. who's popular vote - state vs. nation) is paramount. It's very unlikely the Supreme Court would side with the nation's voices speak louder than the state's with respect to assigning electors

Actually, opposition to these measures would likely be more successful argued in the State's Supreme Court as disenfranchising voters.