>You do not need to abide by UK laws, even if your website is accessible from there.
The UK government does not agree.
All they can legally do is bitch and moan and order UK ISPs to block. There's no action they can legally take against Imgur.
Why shouldn’t Russia be allowed to exert their laws extraterritorially? Or Mali? Or Sudan? Or the Iranians? Or China? Or Israel?
What you’re asking for is the end of the internet, full stop.
It's likely simpler to just block access to the country's IP ranges (or ignore!) and move on.
Except in this case, Imgur does not have a legal entity falling under the UK's jurisdiction. They are purely a US based company. It's not like Google, Apple, etc. that have offices in the UK.
This particular fine is the UK trying to extend its jurisdiction to entities that it has no sovereign authority over.
Just because some UK user might visit my website doesn't mean I now have to follow all UK laws if I don't actually do business there, and don't intend to.
Blocking the traffic is how we end up with the balkanization of the internet.