I think people remember him quite harshly, he wasn't just a finisher, he had good intelligence off the ball too. In fact, he was creative midfielder turned striker, was he not? He was good at getting in the right places at the right time(natural sense for it), getting involved in the thick of the build-up play, knew how to pick a pass etc.
Perhaps his pace and defensive awareness was what made Pep think his future was elsewhere, or maybe it was a mental thing. I guess we'll never know but I still think he might end up a success elsewhere.
He should have gone abroad, Germany or Italy perhaps. The City connection in this country is a hindrance IMO. Or perhaps it's just another move that didn't work out, look at Mahrez who went the other way, he's nowhere near as bad as some City fans make out but he just doesn't look the same player these days. Sanchez at United is another example.