Xmas does work in the PPM areas. It hasn't had the same impact in Buffalo in recent years.
That is because, to synchronize with the PPM "13 Month" system of 4-week measurements, the diary service moved from two un-measured weeks in the Christmas-New Years period plus two other weeks between the other survey periods to the 4 weeks off from earlier in December to just after the New Year. So about three weeks of Christmas programming is lost in the ratings.
But our logical assumption is that the Christmas music station in each diary market does just as well in those unmeasured weeks as the similarly programmed stations do in the PPM markets that are measured.
So your statement is erroneous. Christmas music does just as well in Buffalo... it just is not measured due to the diary system's 4 week hiatus.
I have made suggestions for format ideas, but you dismiss them. They are only suited for Non commercial stations. The results don't lie. When commercial Radio has no room for stations that have a passionate listener base (KFOG in SF was just one example), then the future is dim. Many of these "well researched" formats aren't working. Since Corporate Radio won't invest in trying to sell older demos, the point is moot...
KFOG had been on a long and tedious descent for over a decade, somewhat in step with the changing demographics of the market which is not just over a third non-Hispanic white. So you picked a terrible example because the market for that format in San Francisco simply became so small that the station was no longer on the buy list of agency accounts... and that is a market with limited non-agency business.
As mentioned before, new products, whether they are radio formats or laundry detergent, have a high failure rate. There is nothing unusual for a new format or format variant not to work.
The formats you suggest for older demos are not going to happen. And it is not because radio won't "invest" in trying to sell to older demos. It's because advertisers any larger than small single location businesses have agencies and there is very little or no agency business in radio for 55 and over.
CBS Television has spent millions and millions over the last 7 or 8 years trying to go to advertisers to get them to have their agencies buy 25-64 instead of 18-49. This has been done at the lever of the head of CBS meeting with the head of P&G or GM, not at the lower levels. There has been no positive result. Advertisers look at where brand preferences are formed and where the most product is sold. They don't buy 50+ in TV any more than they used to.
If the TV network that has been the industry leader during most decades of the medium's life can't change advertiser patterns, habits and preferences, local radio stations surely can not do it either.
This is why formats like Music of Your Life, Beautiful Music, Smooth Jazz, AAA have died or are almost dead... they aged out and stopped being attractive to advertisers.