Was Dr. Abraham Erskine's (Steve Rogers') version of Super-Soldier Serum a Successful version?

 We all know that Steve Rogers i.e. Captain America was the first successful super soldier in MCU. We can't even question the honesty and worthiness of Steve Rogers' as we all saw it on Avengers Endgame.

We all know Dr. Erskine is the mastermind behind our beloved Captain America's power. But we all know that after the success of the super-soldier serum Dr. Erskine was murdered and we don't have any proof that the super-soldier serum was successful for others also.

Now the real question arises that Was it a serum or There is something special about our Steve Rogers.

Let's take both aspects.

Unsuccessful:-

1. Red Skull:- We know that Red Skull is considered as a failure of the super-soldier program and we all know that the serum is invented by Dr. Erskine. It turned him into the red-headed monster with more evilness in him. So at Steve Rogers' time, he made the serum and planned that they will expose the volunteer to the Vita rays, but there is no significance explained in the movie, and then after that Dr. Erskine was murdered and hence there is not further proof of the success of super-soldier serum in other victims also. 
   
   
   
2. 
   Isaiah Bradley:- In the series "The Falcon and The Winter Soldier" we can across a person who was another successful super-soldier of the past. Since there is no connection between Isiah's super-soldier serum and Steve's super-soldier serum but an idea that has put in our minds. Isiah Bradley's version was not a successful one but somehow it was successful of him, which indicates that probably there was something special in Isiah. Hence we can also assume that Steve must possess something special in himself.
   

Successful:-

1. Red Skull:- I know it may sound weird but listen to me first. Since Red Skull was considered a failure but let me remind you of the statement of Dr. Erskine that  "The serum amplifies everything that is inside, so good becomes great; bad becomes worse," If we consider that then we can conclude that his red monster body is just a projection of the evilness inside him. Hence it proof that the serum was successful and even steve was special.

Now you may consider these points and conclude your own conclusion.