[Albion Wilde]

I have my doubts. Reminds me of when an Irish-American radio and TV pundit claimed that his father saw "no Irish need apply" signs in the mid-twentieth century. Pure blarney.

It was very definitely a real thing:

"No Irish Need Apply" as were the "Gentiles Only" signs.

Glad the U.S. has moved past that. Here is one man's memoir of growing past anti-Jewish bigotry, helped by his service in the U.S. Army:

‘Gentiles Only’: Boyhood Memories of an Ordinary Bigotry

[Fiji Hill]

I don’t see any phone numbers in the ads with “no Irish need apply” statements, so they’re probably not from the 20th century.