Purists were very sniffy about 20/20 when that started - some still are - but it seems to me it has now taken over from 50 overs as the top short form, nationally and internationally.
The Hundred looks similar to 20/20 to me, although I believe there are some rule differences to keep the game moving.
A team loses a close in fielder for the last few 'sets' if they miss a time cut off - which was clearly news to Bairstow in the last game he captained.
Field changes are not allowed unless the batsmen changes, not such a bad idea because some later overs had become more about the captain and bowler talking to each other than bowling any cricket balls.
Having the women's and men's game the same day makes sense from a spectator point of view, creating a 'day at the cricket' rather like the old 40 over Sunday league.
The telly graphics look garish to me, but it's a good enough watch apart from that.