Nobody is saying use one tool for everything. In fact the argument is why not use PG until you grow out of it (most people won’t).

Agree on devops. Of course.

There’s still the security surface area argument and the overall complexity argument—complexity of the system of systems is NOT reduced by adding technologies.

By way of analogy, using military aircraft, take the F35 vs. the A-10. The F35 is insanely more complex than the nearly indestructible A10 in large part due to the massive number of subsystems, software, sensors, etc. Sure the F35 way more capable (this is NOT a head to head argument about the military capabilities or said aircraft) than the A10, but it also has orders of magnitude more failure modes. More parts. More complexity. More opportunities for failure. This is engineering fact.