Whereas I'm not exactly thrilled by this idea, an extra half an hour is hardly going to effect the amount of those programmes on ITV. There are extensive dramas and factual on ITV. There isn't much comedy but that isn't an ITV specific issue.
Broadcasters don't like "freed up" schedules. They like as much regular scheduled programmes as possible to leave as little as possible to fill with anything new.
Well, I would agree with that. The problem with the soaps scheduling on ITV at the moment is exactly the opposite, though, in that there's a traffic jam of soaps on Mondays and Fridays especially, and then next to nothing the other nights. So even though there's only been one extra episode of Corrie and Emmerdale respectively since 2000, it looks like there's loads more, partly thanks to those evenings when it's all soap. Whereas on Tuesdays after 7.30 and Sundays you have nothing fixed in the schedules so you get some right odds and sods and the ratings peak and trough massively.
As Brekkie pointed out, ITV knows that soaps will be affected by football every two years - now they are playing catch-up, and scheduling miss-placed episodes in odd places - two weeks in a row, Friday nights have Emmerdale at 7.00 and 8.00, with Corrie at 7.30 and 8.30. I think that is relevant.
However, the other general point is that the usual female-skewing ITV audience wants soap, and there may be hours of soap on this and last Friday, but there's also been hours of football for the past few weeks. Ideally you'd spread it all out a bit but that's not possible at the moment. Last week ITV had football in primetime for three consecutive evenings, which is alright for the male audience but did nothing for the traditional ITV audience. So that meant on the nights they weren't showing football they had to aim very heavily at that audience and that means loads and loads of soap.