CHR needs to embrace new artists and songs and sounds that are popular to be relevant. I'm tired of hearing 20+ year old songs on CHR.
CHR is doing what it always does when there is a shortage of good new releases: they reduce the current list and emphasize high testing recurrents and gold.
Top 40 discovered "gold" or "flashbacks" or "oldies" back in the very early 60's when the post-payola years produced fewer solid hits and stations began to fold in at least a couple of oldies an hour.
As research in thee 70s showed, there was lots of gold that listeners wanted to hear and those categories became a standard part of the format; when Top 40 was created and for its first decade, it was just those 40 songs and a few "hitbounds" that were played over and over.
As music went through cycles, programmers would adjust the clocks for more or less currents depending on the number of verified hits and, particularly, the presence or not of "powers". I've been through that and have had times when there were no powers, so the category was dropped for a while, supplementing with a bit faster rotation on the "regular hits" and one or two more recurrents an hour.
On the other hand, there were occasions when there were more powers than normal, and clocks were adjusted to play them all at the top rotation.
Radio does not produce songs. It can not "embrace" stuff that is obviously not going to be mass appeal. It is very rare that true hits don't get "discovered" and played. Today, radio has the advantage of instant play data on songs that emerge out of new media, and it is not hard to spot potential hits. The problem is, to repeat my point, that there is a dearth of good material at times and radio can't make up for it by playing stiffs.