Some people stopped worrying about not understanding compilers. They're not working on drivers, realtime (esp where low lag & jitter are concerned such as motion control), or high performance software of all stripes, trying to squeeze the most out of the available hardware. It's all about choosing the right tool for the job, and there is no right tool for every job. A guy generating sales reports has very, very different needs from the lady writing a rendering engine.

Michael Abrash (graphics programmer extraordinaire) said it best, and I'll paraphrase: the best optimizing compiler is between your ears. The right algorithm beats the pants off the most optimized wrong algorithm. Or, as i like to say "there is nothing faster than nothing" -- finding a way to avoid a computation is the ultimate optimization.

And managed memory is wonderful, almost all the time. That is, just until the GC decides to do a big disposal and compaction right in the middle of a time-sensitive loop causing that thing that "always works" to break, unpredictably, due to a trigger based on memory pressure. Been there, done that. If it's a business report or a ETL, big deal. If it's a motor-control loop running equipment, your data or machinery is now trash.

For most of the programming world, and I count myself in this group, the highly abstracted stuff is great. Right up until the moment where something unexpected doesn't work then it turns in to a cargo cult performance because it's nearly all black-box below. Turtles, all the way down.

There is value in understanding the whole stack, even today.