On Linux, you can set up a Compose key, after which an em-dash is compose, three hyphens (Macintosh: shift-option-hyphen), and an en-dash is compose, two hyphens, period (Macintosh: option-hyphen). Also, a left (resp. right) single (resp. double) quote is compose, less-than (resp. greater-than), typewriter single (resp. double) quote. That’s how I enter them.
You can also (alternatively or at the same time) set up a “Level 3 shift” aka “Alternate Characters Key” aka AltGr, which gets you quotes with one of the English International layouts or quotes as well as dashes with an English Macintosh layout.
Someone recently created some long list of my reddit comments using them as a farcical claim of having used ChatGPT to author many dozens of 2010 comments.
He has a cult following who believe him to be a victim of a lizard jew conspiracy or something and who are quite displeased by people mocking him for continually putting out obvious AI slop. And clearly the people who are accusing him of slopping it up must be doing so themselves... plus then there are people making fun of these people.
Of course, emdash use was not actually a meaningful factor in any of the determination of chatgpt use in court... but it's a signal that even fairly unsophisticated people notice and often presume underlies claims of AI (ab)use.
TLDR: morons consider me their enemy