It seems to me like most don't have a fundamental gut feel for what speculative execution actually is and the implications of "not getting it". At some level we need to fight for performance. My operating systems are only getting slower and shittier. I cannot fathom my CPUs going backwards too. Security must take a back seat at some point. You can't put bubble wrap and warning labels over everything or it becomes useless. The most dangerous tools are typically the most effective.

The CPUs are vulnerable because of the exact way in which they are being applied to a problem. Speculative execution is not inherently unsafe. Whatever future predicted memory prefetching shenanigans are going on in my CPU over here have absolutely ZERO impact on your CPU over there. Certainly someone could figure out a protocol/system/architecture that capitalizes on this notion that "2 different CPUs are indeed different CPUs".

One can see how any perspective here still causes trouble for Amazon, Microsoft, et. al., but that was a business risk they signed up for the moment they intended to squeeze every last drop of subscriber revenue out of the hardware. Why should everyone else on earth have to suffer crappier performance by default because of the business/software practices of a select few?

The only 100% reliable way is to turn off branch prediction completely, and yes, this would make the processors at least 2 times slower, perhaps more.

Too bad that apparently nothing came out of the Mill architecture. My limited understanding is that this architecture would not have such vulnerabilities.

Of course it's possible it would have others :-) but being much simpler, at least conceptually, perhaps it would have less and easier to mitigate. Oh well.

Yep it's almost like Moore's Law in reverse.

Agreed, and I wonder if we'll see the adoption of "security hardened" CPUs which sacrifice performance features for non-exploitability. You can have one or the other, but not both.