It's specifically for "jobs in sectors like agriculture and construction", not sure better buildings will help the workers out on fields and construction sites much.

Although one temperature threshold probably don't make much sense, a strict 30C across the entire continent would mean massively different things in different countries, in many countries that mean basically the entire summer off, every year.

It's not clear from the article, but I think it's obvious they are referring to jobs that require being outdoors

Most places in the south already have AC

And the ones that don't have it, oh well, too bad :)

The south of what?