The same cannot be said legitimately about Bibles in hotel rooms, no matter how long they have been there. Just being used to something does not automatically give it historical value, especially not when it is specifically about a religion (the Bible is connected to Christianity, while God can be pretty much the god of any religion).
You cannot show this "1950s" thing you keep attempting to claim. That has absolutely little to do with whether something is acceptable. Pretty sure children were learning about the Bible and Christian beliefs in school long before the 50s and those still went away.
Frequently Asked Questions - Religion | First Amendment Center
This is the real test of acceptability:
Nothing whatsoever to do with length of time it has lasted.In its 1971 decision Lemon v. Kurtzman, the Supreme Court set forth a three-pronged inquiry commonly known as the Lemon test. To pass this test, thereby allowing the display or motto to remain, the government conduct (1) must have a secular purpose, (2) must have a principal or primary effect that does not advance or inhibit religion, and (3) cannot foster an excessive government entanglement with religion.