Why are people so stupid these days?

Its called rhetoric. It takes a very articulate person to know how to effectively and persuasive use of the language. By being ambiguous allows you not to be held accountable because you are uncertain or indefinite of what is the actual result or how things are going to play out. Even whether it is going to happen or maybe even not. It just shows not being blunt, direct and arrogant *

To some extent I agree with you -- political correctness had produced or encouraged a certain kind of stupidity. However, it was also a response to a certain kind of stupidity. Political Correctness developed because there are people out there who have no human decency or tact, and who would openly say seriously offensive things about, or to, women, people of color, Jews, homosexuals, the disabled, etc. Such people needed to be told, straight out, that, NO, such expression of opinion is not at all acceptable.

Actually I think you would have a hard time arguing that Political Correctness is a serious factor in people getting dumber, over all.

"When I say "take extreme caution!" I am saying there is potentially danger but I don't know so be careful"

No you're not. Saying "take extreme caution" is the SAME EXACT THING as saying "This is very dangerous".

I don't know why you have a bugaboo about this, but I don't know a single person who would be stupid enough to think that "take extreme caution" does not mean "This is dangerious.

You take caution around dangerous things. You whining about this is really no different at all from PC people who whine about saying "undocumented citizen" instead of "illegal immigrant"

There is no such thing as political correctness. It's a term invented by rude people who don't care about others.

It's mostly a matter of semantics, however, not much you can do about it except apply your own choices in your control and not worry too much about the rest.