Last study I've seen, that stopped being... I won't say true, but I'd say that it stopped being a valid counterargument to that particular complaint. Now that young people can access music from any time in YouTube, their choices are more atemporal and certain remote decades keep getting much love.
If you combine that fact with current music being more marketed and aired, there's seem to be something at play here. I don't think new music is crap, but it's less catchy.