I guess that could indeed be annoying for reading code, especially if the labelled block/loop is very long (I personally usually end up using these for short ne

I guess that could indeed be annoying for reading code, especially if the labelled block/loop is very long (I personally usually end up using these for short nested loops, longer loops usually get broken out into separate functions, and the biggest teams/programs I've worked on haven't been using languages that have this feature). That said, the extra structure/more restrictions of labelled breaks lends itself to compilers and other tooling being more helpful, both for optimisations (although SSA + basic blocks that most compilers now use makes this somewhat irrelevant) and for catching mistakes while, for instance, refactoring. In any case, I strongly disagree that labelled breaks aren't better than regular breaks: the chains of booleans required otherwise are very annoying and error prone.