It seems to me that many 'endurance' bikes are a step in the right direction, and away from the (almost useless) faux race bikes that have been common since the mid/late 80s. I personally see very little value, except for racing, of a bike that cannot handle larger than 25mm wide tires. And even for racing, you'd have to get pretty far up the ladder before you actually get any advantage out of a bike that can only handle 25mm tires, compared to a bike that can fit larger, but has 25mm tires and lightweight wheels mounted.
How many of us are actually at a disadvantage because we have 5mm more tire clearance?

There are also some 'endurance' bikes that still can't fit moderately wide tires, but have a slightly more relaxed rider position. I think time will show these bikes (all bikes that only fit narrow tires, actually) as being fundamentally flawed for the average rider.