The uk au and irish scotish english language different then usa
When i watch usa movie or tv show or speak people from the usa i understood clear the english.
When i try to talk uk or even au....i might dont understood.
So why they dont speak clear english like people in usa speak correct english also in canada you can understood emglish therr people speak clean emglish lamguage.
I think uk should start teach people english same clean clear english as we hear on ghollywood movies when actors talk we understood all clear
It's possible you are more connected to the ones you hear better. If you share similar mindset with a country or you enjoy/like their contents you will likely learn their language quickly. I don't really think deep accents or different in similar language is the issue.
Back then I enjoyed the British English because of BBC but when I started knowing things that should never be known by foreigners I started finding it a bit repulsive & difficult to understand. Likewise the American English... you tend to like it when you watch their movies but things begin to change when you interact with them or watch their independent contents on the internet.