I hate to be going full pedant, but you are wrong.
I have read the Truth, actually, though it’s cute that you assume I haven’t. :) And by cute, I mean really shitty of you.
In the Truth: Red, White, and Black, yes, it was originally made clear that Isaiah was not the first Captain America. The dates establish that very clearly in The Truth. In The Truth, it is very clear that Steve is already active by the time Isaiah comes along. The Truth makes it very clear that Isaiah was an attempt to recreate the serum.
Those are true things.
Now there are obvious reasons for that, and not because of logic or historical sense. Do you know why it is very likely that it changed from the proposal to the issue of the comic book? Because it is a matter of fact that comic book whiners bitched and moaned (the same way they are now) about how the sanctity of Captain America was being ruined by a black man being Cap, and the idea that Steve Rogers had become Cap after Isaiah was too much for them to handle. So Marvel gave in. Now that’s speculation.
But here is where FACT comes back in:
Here is the thing: you are talking about COMIC BOOKS. We have these magical things called retcons. If you are familiar with Captain America, you must be familiar with the concept of a retcon because everything you have read since he showed up in Avengers #4 is a giant fucking retcon.
Everything since Brubaker came along is an even greater fucking retcon of the established retcon.
So I’m going to not be as condescending as you were and I’m going to assume you’re familiar with Cap’s history and comics as whole and therefore understand what a retcon is.
Two retcons have made the facts established in The Truth unimportant. Those FACTS are that two other series have retconed Isaiah into being the THE FIRST Captain America.
Both The Crew and Young Avengers tell us that The Black Captain America was the First Captain America.
Now, you can stubbornly cling to the original story. You can.
You can do that and I’m going to judge your motivations as surely as you judge my ability to read a goddamn comic. And here’s why I’m going to judge your motivations, precious:
You are basically laughing and calling Isaiah’s son and grandson liars. You are basically scoffing at the history that those black men present to us and saying “Nope, sorry, he wasn’t the first.”
According to the magical rule of retcons, yes he goddamn well was.