I think it's worse than it's ever been. The only plus side is at least they aren't mosquitos or some other bite-y bug.
I am not at all in favour of fly sprays. They squirt chemicals all over the place and, anecdotally, don't actually work.
I did some
However the boy did not seem think this was good enough - probably because all the flies seem to be in the house already.
So he went out to and bought some fly paper (above) and a fly-catcher (like a dream catcher but icky-ier) (below).