Why is this a new thread instead of in controversial?
Regardless, invulnerability or the lack thereof has nothing to do with someone being a 'jobber'.
Both Snyder and King had the entire Justice League get effortlessly curbstomped to hype the Joker and Gotham-man as big deals.
Superman was effortlessly defeated by Ultro- I mean Fail-Safe in the most recent run just to show how dangerous a threat the villain was.
Batman vs Robin had Damien defeat all the worlds magic types as build up to a plan to defeat Batman which included Fate, Circe, and Le Fay.
King had Harley Quinn defeat Batman, Superman, and Wonder Woman all at once in Heroes in Crisis.
If someone has a reputation for being strong, they will get used as fodder to show how tough their counterpart is regardless of what the scouter says on their power levels. Deathstroke WILL defeat Superman in the Deathstroke book. Batman will defeat the entire Justice League in the Batbooks. In a story where Catwoman is the main character she will defeat Cheetah regardless of the power difference.
Writers don't look at things with a question of how invulnerable someone is or how many powers they have. They look at what best sells the character their writing and works for the story and will make it work regardless.
Make Wonder Woman invulnerable? Sure, you can do that. Though that will just mean Deathstroke will once again have a godkiller sword that can wound her anyway. Or Katanas Katana will slice through regardless. Or Ras will have some macguffin that nullifies it.
You can give a character as many feats and powers as you want. It wont matter if a writer wants or needs a story to go in a certain direction.