As I said in the OP, 'Operational Reasons' is meaningless, you are as well just saying 'Your flight is delayed'. The anodyne (often prerecorded) 'This is due to - pause - operational reasons' just grates.
I've been unlucky this year as I've had three flights cancelled (all returns), one due to the severe weather in March, the one I wrote the Op whilst waiting for (Which was because the delay led to the crew being out of hours) then most recently one caused by a late running service due to an earlier medical emergency then a weather cancellation due to strong crosswinds at BRS. In 18 previous years of regular airline travel, I've probably had no more than that in total. These things happen, 6 out of circa 1K isn't bad (and number of severe delays >2hrs probably in low teens at most)
That does bring up another area - the amount of info the airport gives you - in the latter case, I was able to see exactly how delayed our flight was on the easyjet app/website, whilst the boards at BRS were either saying on time or giving a ridiculously low delayed time, right up until it suddenly jumped 2 hours (I knew that already form the App) and yet if you question the airports, they say they take it directly from the Airline feed! The app even gave a full explanation as to why the delay!