The problem is that the writers are normal humans.

Imagine this: let’s say the writers themselves do understand the highest level of competence. They write the Voyager crew in a way so that they handle all issues perfectly. How would it be possible for them to come up with any situation where this Voyager crew is challenged? - they can’t. Because they are portraying them as perfectly competent, which is based in the writer’s imagination, the definition of this perfect competency is that the writers could not come up with a way for them to be challenged.

Hence, when making any story like this, it is absolutely essential that the writers leave a flaw that the writers know about. Otherwise they literally would be unable to come up with any challenges. So the characters in Voyager necessarily need to be less competent than the writers.

But since the writers are average humans, the characters necessarily end up being less competent than average.

Maybe you didn’t see it before because TNG and DS9 actually taught you things, but those shows were the same. Most issues in those shows are ridiculously badly handled.

The thing is, it’s not actually that important that the characters are competent in actuality. This is where your suspension of disbelief comes in. You just have to believe for the context of the show that the characters are actually super competent. The story is mostly still valid and focuses on human growth and interpersonal relationships, which would be pretty much the same if the situations portrayed would actually be handled better. Even though the characters are not actually competent, you can act as if they are and then everything works again.