In fact, I think this may have been in response to many customers who had to wade through a ton of channels to get to where they want. Keep in mind, a lot of subscribers like to use the Page up and Page down while in guide to see ALL the shows they can view without accidentally skipping desired channels by jumping around by keying in the channel number, and many others just REFUSE to even attempt to make a custom list. That's just the way people are. The collapsible channels is of tremendous value to many who don't want to wade through the Sirus/XM, etc.
Be aware, that if you place your pointer (or highlight) on the collapsible position, it will automatically expand, so you don't have to press any buttons to expand.
As for me, I wish they would use expandable/collapsible on MORE of the guide, and I would love it if the channel numbering convention also were like the collapsible such as all the ESPN being 140, 140-2, etc. and also for all the kiddie or Disney channels and all the the premiums as -2, -3, etc grouped by providers. That might be better than even adding more custom lists, but I would love to have more custom lists, as well.