The secret identity is really necessary? watching shows like

this better be b8

Well, one of the innovations of Marvel in the 60's and 70's was the eschewing of traditional superhero elements, such as the secret identity.

I wouldn't say it's an antiquated idea, but it's not needed for every character. In the 70's and early 80's they found that Iron Man and Thor both worked better without the secret identities. At the same time Batman and Superman spent a lot less time on plots involving the secret identities, and characters like the Flash revealed themselves to people close to them.

But then you have characters like Spider-Man where the secret identity is absolutely crucial to the character and they wouldn't work without them.

Ironically writers later found that there was a lot they could do with Superman and Batman's secret identities, such as Bruce Wayne being a proactive and smart political figure instead of an airheaded socialite, and Clark Kent doing investigative journalism to go where Superman can't.

Ultimately it comes down to implementation. Like you said it can be an excuse for cliched phoned-in plots, but it doesn't have to be.