That was my first thought also. Didn't say it but it crossed my mind first. Look at XDR icon. It has the same bezels (on the icon) as iMac and iMac Pro and yet the reality is completely different. If they draw the icon correctly proportion wise it would look super bad. It just wouldn't work as an icon. So to me, the fact that icon exists is super good news. No chin is good news.
The fact that it has got huge bezels is irrelevant as I KNOW that it doesn't represent the real product.
Also, Apple often puts placeholder icons and then tweaks them later.
I wouldn't be surprised if this was intentional (as Apple often does it) to create even bigger buzz for WWDC! Its basically free marketing for them. Provide enough leaks to get the media/forums/youtube talking about it and creating a buzz around it. Then go on the stage and deliver something even better.
Of course, when there are genuine uncontrolled leaks then that is where Apple gets pissed off as the element of surprise is gone.
Imagine if there was no interest about potential stuff at WWDC and it would be truly developer based conference. Most people would simply not even know that there was something from Apple.
So Apple doing these "controlled" leaks basically draws bigger crowd which means more customers as their keynotes are truly polished and I often feel like 'instant buy'. When everything leaks before or when I get a week/month pass by I realised that I was a victim of marketing and I get back my senses and don't buy anything.
Or I do and then return in in the 2 weeks period. (just like i did with iPhone 11 Pro).
Value is what I'm after. Not cheap, not expensive but just good value for my money. This iMac better ducking fusion sake delivers otherwise I'm in trouble