As is their injury record.
I don't agree with this. We do get injuries but not to players you would class as key. Salah & Firmino have had minor knocks but Van Dijk is always fit. TAA and Robertson have also had minor knocks here and there.
Alisson missed the first two months of last season, Fabinho was out for a long period, Henderson's been in and out, Gomez and Matip have had longer term issues over the last two or three years and some other players have been in and out. Chamberlain's got an awful injury record as has Shaqiri.
We do get injuries to players.
The thing is though, why do people talk as though we're supposed to be getting injuries to these players? City have had injuries to Laporte but they weren't supposed to. It's bad luck that normally doesn't happen. How often did Chelsea lose Terry, Lampard, Cole or Drogba for long periods? How often have United been without key players during United's era of success? How many games did Ferdinand, Vidic & Ronaldo miss during 07/08? Teams aren't supposed to lose their key players for extended periods.