It's impossible for us Brits to say "well that went well" without sounding sarcastic. Even if it was meant positively.

😆True

When was the last time something "went well" for the Brits?

You are right, but I think it is the use of "well" at the start of the sentence that does it. Think any sentence, for example "That was a great holiday" and then think "Well, that was a great holiday"

Unless you use it as an understatement when things went exceptionally well 😄

I always felt that it was a gentle and mildly humorous suggestion that things hadn't gone well. Maybe that's just our British heritage.

To be fair, how often do you actually mean it positively?

British people often sound like entitled brats to me xD

Facts

No