Even Aston Villa owner Tony Xia acknowledged it in response to a tweet about old misery guts after the Bristol City game.
Fans observed that as Jack Grealish and Co celebrated the youngster's early goal in the defeat at Ashton Gate, Ayew just trudged away without a flicker of happiness.
His demeanour has prompted closer scrutiny this season than last after a summer in which he was linked with a move away from Villa and in which he slid down the attacking pecking order.
From being the main man in a team of relegation no-hopers he is no longer first choice in a team of promotion hopefuls.
He might have started all six of Villa's fixtures so far this term, scoring in the EFL Cup defeat at Luton Town, but following the arrivals of Ross McCormack, Jonathan Kodjia and Albert Adomah his place as an automatic starter is no longer a given with Roberto Di Matteo expected to favour his own signings.
There have been rumours in recent days that the Ghana international came close to returning to the Premier League with Crystal Palace in the closing stages of the transfer window.
Whether that is true or not it no longer matters.
Ayew did not move and he remains a Villa player, until January at least.
Now it is up to him to summon up the spirit of last season.
He was a nugget of gold in a stream of...erm... mud for Villa last season. Yet I can't recall him ever playing with a beaming Dwight Yorke grin on his face.
Even when he was becoming last season's top league scorer (admittedly, an achievement as impressive as being Snow White's tallest dwarf) he was hardly grinning his head off.
And while we're on the subject of Grumpy, what he did do in the forgettable relegation campaign of 2015-16 was ignore the malaise around him to knuckle down and try to positively affect matches - most of the time.
We shouldn't read too much into the striker's surliness.
That existed when he was producing encouraging displays last season and when he was convincing the claret and blue faithful he was a player they would be loathe to lose.
We all love the idea of players playing with smiles on their faces, but Ayew just needs to suck up whatever frustrations he is feeling and strive to put a smile on the faces of supporters.