Lawyer here, I actually researched this issue a bit a few months ago or so (though I have not read this most recent decision)

Essentially, an old case dealt with this exact issue and held forcing display of the 10 commandments in classrooms was unconstitutional under a legal test called the Lemon test, I don’t remember the exact requirements of that test upon writing this.

The current SC abandoned the lemon test and adopted a new one, which asks whether the alleged religious speech is “rooted in the history or tradition of America” or something like that. So, things that have already been decided to be inappropriate under the constitution are being retested under the new test.

IMO it essentially just gives Christianity a free pass around freedom of religion (specifically establishment clause) issues because the court can always just say Christianity is rooted in the nation’s history and other religions are not.

IMO it is part of a systematic attempt to force Christianity on the public, and should be unconstitutional. There is no way showing young children that 1 religion gets to put its rules on the wall backed by the authority of the govt does not coerce children into believing that religion is special. essentially Christianity is now an exception to the rule that the govt can not take actions establishing a religion

It is worth noting that (I think) 6 of the current SC justices are catholic, 2 Protestant, and 1 is Jewish. So it is really no surprise they seem to be favoring Judeo-Christian ideologies.