No.

If you worked in Hong Kong, failure to speak Cantonese would be a big obstacle for promotion. You would have a lot of difficulty if you don't speak Cantonese.

It is as simple as this:

Mandarin is the dominant language in some regions, and you must be fluent in Mandarin to do well in those regions.

Cantonese is the dominant language in some regions, and you must be fluent in Cantonese to do well in those regions.

In fact, Mandarin and Cantonese are not the only languages spoken by many people in China. There are other spoken languages in other regions.

The only thing which makes Mandarin different is that the region where it is dominant is larger than all the other regions, and that it's the official govevernment language.

Of course, in places where the dominant spoken language is not Mandarin, government officials speak the local language too otherwise they could not do their work.

You talk of "clamping down on language other Mandarin" like that is a good thing.

Human languages don't work that way, and trying to force it is not kind. Take a look at history and geography of languages around the world! Lots of countries have multiple languages. And lots of languages have multiple countries.

Cantonese is the native language of Hong Kong people. It is not new, it has been like that for a long time. They are as clever as you, they have just as good lives, they just speak a different language in that region.

You want them to speak Mandarin, even though it is not their native, local language? Even though millions of them speak Cantonese fluently and prefer it?

And then you complain when you think people are forcing you to use English or other European languages! It is the same thing!

Don't you recognise the hypocrisy and irony (contradiction) of your words?