I think the "message" is actually racist, as much as age-ist. And it is invalid to compare songs from disparate genres and eras.
I'm not sure where you are getting racism from.
Well Beyonce is black while Freddie Mercury is Indian but was often mistaken as white, so this might be implicating that Beyonce's song is... Dumber because she is black (and possibly others who worked on the song as well.)
Then again, I think it could be just another complaint about how "modern" music is stupid and simple. Which is blatantly false as there have been simple silly songs since the creation of music and you'd find similar examples of complexity and quality from any era and genre.
I think folks make these complaints about music like that due to the ol' "Nostalgia Filter" (as TV Tropes called it). Actually all generations have had good, complex stuff & goofy stuff.
Heck, look at some of the "good stuff" of yore and the themes are simplistic dorkiness. Led Zeppelin was an amazing classic hard rock band and oft-cited as "the good stuff". But the lyrical themes of many of their tunes were on par with Warrant's "Cherry Pie" (Y'know, the 'Hey baby! Y'drive me crazy! Baby baby! Let's get sexy & roll in the hay, baby! etc.' stuff).
Likewise, the "good ol' days" were loaded with their own teeny-bopper, plastic pop schlock slop: Fabian, Pat Boone, The 1910 Fruitgum Factory, David Cassidy, Shawn Cassidy, The Osmonds, The DiFranco Family, Leif Garrett, Menudo, etc.
Even some good bands started off as basically "Boy Bands", yes, even THE BEATLES!
Taste is subjective and while some folks utterly adore stuff that's dorky & empty, I'll still respect their right to enjoy it. If someone's into jamming to the usual "New Insane Clown Fergies On The Nicklebackstreet Biebers" or reading "The Fifty Shades Of Edward Cullen's Nude Anita Blake Photo Collection", who am I to judge them as a person?
If I find someone's tastes goofy, I might express it but I wont obsess over hating on it to death. I have better things to do.
The above Beyonce lyrics are dorky but even John Lennon did the same thing once. Ever heard of John Lennon's protest anthem,
Power To The People? Even he, after a while thought it was waaaaay too dorky, repetitive & simplistically written.
That said, Beyonce's girlpower anthem & Lennon's peacenik anthem were meant to be sort of something to get in your head as an earworm (I confess Beyonce did a stupider job, even Lennon added some variations, plus Beyonce's song seems more 'female-supremacist' than 'feminist').