The protagonist should be either capable of potential or competent, in my opinion. Tired of farm boys or fresh-eyed cadets out of Star Federation academy, the protagonist is often the central figure in your work but not always. They grow, they transform, they get crapped on by seagulls. Maybe they’re a work in progress, picking up additional skills like how to balance a sword while chopping off an undead’s head at a 90 degree angle, or maybe they’re already a master-at-arms in their Lady’s militia.
However, a critical mistake, I’ve seen too often in fantasy and science-fiction, is characters who bloat toward godlike statures. Now, if this is the purpose of the character, to showcase and detail what a living god functions and acts like (The Kingkiller Chronicles), then that can be entertaining, thought-provoking. It’s been done before. But more often than not, protagonists become walking fortresses. It’s fun, it’s kickass.
It’s also godmode flipped on and no_clip at the same time. Congrats, you have achieved short term awe and spectacle for narrative failure. The minute the protagonist starts absorbing skills other characters excel at, i.e. supporting characters’ skills/roles, is the minute you ruin character cohesion, also known as party synergy. There is a reason why in tabletop, heist movies, and even police procedurals every character has a strength and weakness that is picked up/buffered by another character.
If your MC suddenly can pick locks and infiltrate the Baron du Cheese’s chateau, then your lovable rogue/sidekick is useless. Nix him. The sorceress who can speak with the dead, woops, Hildegard the renegade princess now can raise her mommy from the dead, thanks Lavola for all the help, not. Oh, Master Sergent Reyes, I can noscope the alien overlord, you’re not needed anymore, here’s your honorable discharge. In the process of transforming your MC into a minmaxing munchkin, you’ve denied your supporting cast, subplots, and your own narrative threads their agency.
You have killed your story. Where can you go from there? Even Dune, with Paul being a messianic badass, still is vulnerable/falls at the end of Children of Dune. There are several tricks to remedy this (depowering, some metaphysical death, etc), but you often have little options. You’ve made characters obsolete/redundant and the thrill of the hero being saved by their sidekick, the old mentor revealing she’s a badass kungfu wizard is gone.
It’s ok for protagonists to rely on others, to not be Doctor Manhattan in each story. Having protagonist show ignorance, gaps in skills, logic, knowledge, that builds character, that creates an arc.
Let the protagonist be human, flawed and all.
This Life is Hijacked 