Every technology is designed through tradeoffs. Choosing a technology and the using it properly reqires understanding those tradeoffs. What they are, why they were made. I whine about the appetite for secret allocation that my C# program has. I whine about the mess that is writing the equivalent C++ or Go code, and the learning curve of doing it in Rust.

It’s whining on the surface but it’s really 90% tradeoffs and 10% badness.

Being able to critique design mistakes in eg. an API means you have a pretty deep knowledge on the domain (and/or API design in general). Being able to argue the downsides of a certain technological tradeoff (such as GC vs not, dynamic vs static) is also important. No one will be able to win an argument on tabs/spaces or dynamic vs static but everyone should be able to point out some drawbacks and benefits.

Describing the merits of a technology is just as good as describing the drawbacks. I chose drawbacks/whine because (unfortunately) I am myself much more enthusiastic when describing flaws than positive sides - itself a flaw, but a very common one.