Also, those IBM Selectrics were built like a tank, and they did not fail very often. My family's business had one that lasted for at least 10 years of regular use, without adjustment, even after it was refurb'ed and sold to us.
Comparing the memos available on the CBS News website, one finds the author used the superscript "th" in some, and did not use this special key in another.
That key is a single-stroke special character.
It's the smoking gun to this latest bit of phoney-baloney from an overeager media seeking to prop up another leftie.