The OP wouldn't be raising the term shithole countries if it were not for the president. It's not possible to have the discussion without the present shitstorm surrounding the president's use of shithole countries. The OP made implicit reference to the president's remark in his title's wording, a response to Trump's comment even.
All respect for others can be dismissed as PC, but that doesn't remove respect from being respect. Everything is not reducible to the lowest, meanest, basest denominator, and certainly not as rationalization for anything goes.
A country is as I have stated, a collective of its people, their culture, their government, their production, their religion, and every other thing that comprises their identity. Dismissing an entire country as a shithole is wrong, and no amount of equivocation changes that.
By "knowing what I mean," you don't remove the actual words and their actual meaning. Redefining them doesn't cut it. Sorry.
The president's remarks were offensive. Elevating their acceptance is unacceptable. Speaking about other countries in that vein is unacceptable. Alleging that "everyone" thinks like that is simply untrue.
I don't want to live in Canada, or Britain, but I wouldn't judge either as an undesirable country, just not one I want to live in. That test is not the measure of a "shithole country."