I feel people have less of an issue with the change in format than they do with the titles of the newscasts. Some of these new ideas are rough, yes. Historically (probably) these shows don't seem to have a high success rate, but I blame that on there being a bunch of young Baby Boomer and old Gen Xer executives thinking they understand the younger generations more than they really do or abandoning an idea when it doesn't return immediate success. Plenty of young folk appreciate long-form, serious, investigative storytelling. The problem is local TV doesn't have time for it.
And like many other things on the internet, this forum ignores successful new ideas/takes in favor of those that failed. What's an example of a station that radically changed a newscast and actually saw success from it? I don't know because I only ever hear about the failures.
I'm rambling, but the point is...
How will you know if an idea to shake up the status-quo will work if you never try it? News is like investment - every once in a while you have to take a risk. It'll either pay off brilliantly and you look like a genius, or it fails miserably (and embarrassingly) but at least you now know what doesn't work. One newscast will stand out from the rest and either viewers will like it or not. Finally, it IS possible to keep a traditional newscast but change how it looks or is presented. Something as subtle as changing the lightning can make a huge difference in a newscast's mood.