With HTML, I can do everything as a <div> and the eyeball reader doesn't know/care. Where it matters is that I'm stripping semantic meaning, which hurts computers and possible accessibility devices.
Most of my life, the same has been true about dashes. I use - for every one of the kinds you provided because - lives on my keyboard.
Is there real value in caring? Does it have the same semantic—stripping effect for computers/accessibility devices? The part of me wondering if I really should care is trying to suss out if this is a real problem or just an argument for semantics pedantics.
I can't think of any case where a human gets confused by some text because a hyphen character was used instead of an em-dash, and maybe that's what you mean by real value.
But I see you using an em-dash to hyphenate "semantic-stripping" as a joke, which is funny. Is that real value? Is conveying to others that you're educated real value?
Yes, it matters. I found your comment hard to read and had to re-read it a couple of times to parse it. If you want to use the hyphen because it's more easily typed I suggest using the double hyphen "--", which perhaps doesn't have the correct semantics on a per-character basis, but at least looks mostly right and will be clear in meaning to a human reader.
Only when responding to rants, i.e. pedantry for fun. Live a little!