For a superhero appearance to come off as something you might see in the world and believable (i.e., not wearing something that seems easy to be torn considering the life of a superhero).
Top row:
Dick Purcell from the
Captain America 15-chapter serial (1944). While some might say,
"all comic-based costumes were terrible back then", the costume from
The Adventures of Captain Marvel--for one example--was and remains an excellent take.
Reb Brown in the costume worn in the
Captain America II: Death Too Soon TV movie (1979).
Bottom row:
In a post-Burton world, there was Matt Salinger in the rubber job from
Captain America (1990).
Chris Evans in the costume worn in
Captain America: Civil War (2016).
I believe most would agree the not-so-simple MCU version was not only visually more appealing, but made practical sense as a believable uniform capable of weathering most forms of abuse heroes must endure. the same argument can be made for some--but certainly not all--current superhero costume designs.