In this case, Theresa May presided over the Home Office before she became PM, and spent 6 years promising to cut immigration but instead of actually doing that in a transparent way with quotas etc. that would open the door for discussion about whether or not said rules were right, she instead did her best to create a hostile environment for applicants instead. This practice has continued in other areas of government under her leadership, such as the benefits system. It's a fairly uniquely passive aggressive approach to government that seems to take Kafka or Gilliams Brazil as a recipe rather than a warning.

The British Prime Minister made a completely unfullfillable promise to bring down immigration numbers - despite the he country being part of the EU and thus having free movement making it impossible to hit his targets.

Because this mistake cannot be admitted the civil service is trying to hit impossible targets amd as a result cases like this occur on a daily basis as they look for any possible reason to deny an immigration case.

The same reason that people living in nice neighborhoods with nice houses don't invite all the people living in the slums to come live with them. This happens in non-English speaking countries also.

Dunno. They might just be more popular destinations to immigrate to, being (mostly) stable and rich, and English being one of the more common second languages around the world.

Nope, try emigrating to any country and see how un-dickishly they behave. Switzerland, for example.

Immigration is not easy anywhere, and I'm always surprised when people assume it will be - or spend decades not sorting out their status, then cry to the media when they're threatened with deportation.

Others aren't much better frankly. The German process was pretty much "Sit tight, don't ask for updates...oh and it may take 2 years" (It did).

Canada seems to be the exception to the rule. I heard Australia was similar but they're clamping down now.