Meltdown looks pretty much like cheating. Intel simply took security verification out of the critical path, and their public image ought to suffer for that.

Spectre is a much more complex issue. It is more of a "I would never thing of that" thing. Looks like there were people at the security community talking about it even 10 years ago, but it is certainly hard for knowledge to spread to chip designers - most of what security people study would be noise for them, and even the security people mostly ignore those.