I think CMC wasn't wrong to do what they did.
But the issue isn't there. Lots of organisations get shat on when doing the right thing. It's human nature.
I just think they should've put more effort into smoothing it up. They could've announced it beforehand, or even added a note at the top of the main page so you couldn't miss it when visiting the site.
The real issue here is how important those big organisations (exchange platforms and market info) in the course of cryptos. A small mistake from theirs can create a bullwhip effect, which is basically a small mistake turning into a bigger one down the line. So a little mistake like CMC's can turn into a massive sell-out.