What I've seen, besides the obligatory promotional stuff from Nikon and a few hands-on reviews, are articles by people who are saying these cameras already suck. Is it about clickbait? "Oh, it's just a mirroless 850/5D Mark IV!" Uh, what did you expect?
It's only got ONE card slot!!!! OMG, How many years did we shoot with one card slot???
These companies are just entering the mirrorless waters seriously. And we've only seen one of Canon's proposed cameras. Give it a little time. Honestly, I wouldn't buy the first round of mirrorless cameras from them because I'm sure there will be some bugs and growing pains. But, it doesn't mean they're terrible https://mobdro.bio/ https://kodi.bio/.
Yeah, the specs are similar to the DSLRs that already exist. Were those terrible cameras? This is what you might think of as a bridge between DSLRs and Mirrorless for these companies. Yea, you can still use all your old lenses. Yea, the specs are pretty much the same.
Everybody jumping to hate on them before they've been seriously tested in the field is kind of missing the point of what they're for...