-5°C to -2°C

post-war - pre-digital era (not a sentence any sane person would use anyway).

See sections 10-O - 15-Q

Try our New York-London flight connection! (no kind of dash clears this one up without fixing capitalisation).

The last one was a gotcha: it's their newly established York–London flight!

Try Our New York–London Flight Connection.

Or if it was New York:

Try Our New York – London Flight Connection.

Note the additional spaces. Agree on the capitalization though.

> Try Our New York – London Flight Connection.

I'd wager serious money that if you put that on a sign and surveyed people, at least in the US, they'd all still conclude it is a "New York" to "London" flight.

What's the use of a communication tool, if it doesn't actually communicate anything to real people?

York doesn't have an active airport

In my region at least, -5 ~ -2°C, or -5°C ~ -2°C. If the something is making people confuse, we replace it with a suitable substitution. Re-educating people is really just last resort. Is there anything keeping us from changing it other than ego?

In all countries I've lived in (and until right now, I thought the entire world), that would mean "-5 is approximately equal to -2".

Have you heard of "to"?

Sorry, lol? You didn't really think this through. This is what that looks like using en/em

-5—2

That looks like dogshit.

It's a mistake in the first place to decide to use only dashes and no spaces to convey all of this lol

-5 - 2 (Everyone knows a sign has no space - if you are building your sign for idiots try some of these:)

-5 > 2 -5->2 -5 <-> 2 -5 to 2 -5...2 Between -5 and 2

blah blah blah

-5 - 2°C

= -7°C

HTH!