Personally I think people are bitter at how his time here went. We all know he was brought here to win the CL. The bitterness is likely towards Ronaldo for not really making the difference but also management team for some incredibly questionable decisions (including the dining and the financials in the first place)
Ronaldo made all the difference he could ever had. Man, i'v said multiple times, we tried to win with the old core, for the guys like Chiellini etc. but it was never meant to be really, and we don't have Buffon in here, Chiellini's gonna retire soon, Mandzukic is gone, Pogba is gone, Marchisio is gone, Vidal is gone and so on. We tried to do what other big clubs tried to do, which is to buy the success and not many of those teams have succeed so far. Ronaldo literally prolonged our chances for extra 2-3 years, while our team being full of these Matuidi's, Khedira's, Bernardeschi's etc. Even we didn't win UCL, people believed we have the chance - which wouldn't have been the scenario without him. He came in the worst possible time in here. We just sold our mid and we were getting older, so it was just massive piece of ducktape to fix the water leaks, which didn't carry till the end. People shouldn't be dissapointed about it, they really shouldn't. Shouldn't forget the Atletico comeback, which was quite exhausting night and im sure many people in that night, grew even little bit symphaty towards Ronaldo. The success didn't come in RM right away, it took little bit of time and we just didn't have the time really and we tried to win straight away.
Our desperation towards UCL is understandable, but City hasn't won it by spending a billion. It will come, if it will come. There's no favourites really and it just comes together if it comes. I don't blame Ronaldo a bit for not making it happen in 3 years, which is nothing compared to 25 years.
Im sure there's even little bit of black n white in him and his family will remember the time in here, including his son who spent years in our junior teams. Maybe he will remember Turin and Juventus from the time his kids said their first words or learned to ride a bicycle. Doesn't really matter and these 3 years, i felt something different than i'v ever felt at certain times seeing him play for us compared to any other player. I just felt the greatness and that's the reason im watching these games, these different sports to see things, that hasn't been done in the past or someone just being so good, that it leaves you in awe of the capabilities of humans.
Don't be bitter, we have great history and we will rise again.