It's a question of what should be addressed first.

Linus is actively arguing against a faster kernel build. It sounds like it makes sense, because it gives him leverage with CPU vendors.

But it doesn't, really. If kernel build were already fast, he would never in a million years slow it down just to get that leverage.

Now maybe he's perfectly aware of this status quo bias, and he's taking advantage of it to meliorate something he would otherwise have no power over. Sneaky.

Still, what's the priority? He's made his point now, hasn't he? He could work on making a faster build process, now.

Slowing it down wouldn't give him the same leverage that it has as a real use case.

Anyway he's not saying slowness is better in and of itself, just that there are better places to work on than replacing make.

Actually, his main point is "here is a workload that is kernel-bound that ordinary users deal with, and here is where the time goes." He has explained in the past that he works on whatever interests him, period. So profiling page faults must be more interesting to him than speeding up the build per se. That's all.