[Python-ideas] Re: concurrent.futures cancel pending at Executor.shutdown

But, it would potentially risk adding an underutilized parameter to the executor constructor (which contributes to feature bloat).

That's true, personally I would always enable cancel_on_error (making it redundant and implementing it in the abstract class), but that's just my use case. You can always add that functionality later with your own subclass.

Personally I think it make sense to do it by default but that's just me and it also changes current behaviour.