You can certainly call it my bias, but again, I think a champion has a few excuses. I think of it this way... when I lose a tournament game against a player who is clearly weaker than me, I'm upset. I don't mean a lower rated player, I mean a player who I can tell is weaker by their generally inferior moves.
For a dominating world champion (of any sport), this is nearly 100% of their games... so nearly 100% of their losses are painful... plus champions tend to be young, they lack life experience in general. So ok, they become upset. I think it's understandable.
In my mind this is very different from e.g. Hikaru being upset after losing to Carlsen. By every metric Hikaru is clearly inferior to Carlsen, so he doesn't deserve to be upset. It's just the natural order. Sure he can be upset for failing to play up to his own standards, we all have bad days where we disappoint ourselves, but e.g. the Sauron tweet isn't about reasonable standards, it's about blind idiotic arrogance.
It's understandable, yes, for Magnus to expect domination, and to get angry when he lets games slip away.
Though I believe Hikaru's tantrums get a bit over-criticized, too. Often, it's quite obvious that he's angry with himself, for missing things. Not necessarily petulant that he didn't win, but petulant that he didn't see things that turned out to be so obvious (to him) in post-analysis.
He's emotional. Competitive. Doesn't handle losing well. That's just who he is. I find him a bit Diva-ish, but hardly the "toxic" person that some players describe him as.
The way he's described, you'd think he's strutting around like the Connor McGregor of chess, or something, hurling insults and swear words at everyone under the sun ...
Also: Hikaru's Sauron tweet didn't age well, that's for sure.
Though I believe he was talking about his 2013 Sinquefield Cup performance (since his tweet came relatively soon afterward).
At the time, Hikaru was #4 in the world. And the Sinquefield Cup was the last real tournament before Magnus' World Championship match against Anand.
There were 4 SuperGMs in the 2013 Sinquefield Cup: Carlsen, Nakamura, Aronian, and Kamsky.
Aronian and Kamsky both fell to Carlsen. Nakamura was the only player to hold Carlsen to draws.
So it seems (to me) that Hikaru felt that he was the only top player who could go toe to toe with Carlsen, without crumbling. He saw Anand falling apart against Carlsen, and thought, "Well, crap, I held Carlsen to draws, no problem, just a few weeks ago. I guess I'm the only guy around who can handle Magnus."
Wishful thinking, yes. Especially considering their lopsided head-to-head record.
But I think the context of that tweet gets lost in the re-tweets. And the internet seems to have no intentions of ever letting Hikaru forget it ...
I don't like or dislike him, I don't know him...
I do like how he plays his chess and how he tries to bring our great game to the masses...
But why would I judge him personally on how he handles what is, a game?....yes a fantastically brilliantly subtle game with many many depths and dimensions......but still a game.