The em dash was in popular use long before chatgpt. It's a useful grammatical symbol and a short dash is not a good substitute. Consider whether you'd use it if it was a dedicated key on your keyboard, if so then it's worth the small inconvenience to learn how to type it.
Not just the em dash, the whole post stinks of ChatGPT, and there are two other obvious tells in the sentence I quoted.
If you know you know.
Fair enough. I'm sensitive about the em dash being used as a tell, which I've seen mentioned once or twice, because I don't want people to dumb down punctuation to avoid being confused for an LLM. I'd guess it's a temporary issue until the LLMs get so good at blending in that we can't tell anymore.