A quick google search reveals that it's not quite a clean cut as all that. The species are different with unique strengths and weaknesses. Some are more difficult to play effectively than others and in order to win a competition you need to have the correct strategy for the chosen species.Star Craft is repeatedly held up as a great example of asymmetrical balance. Like, this is something all over the internet. "They get pretty close" is exactly what I'm talking about.
Because you keep raising this strawman of perfection. That it must be perfect balance, utterly unassailable under any context no matter how bizarre. That is false, and always has been.
It's not a matter of disliking the argument. It's a matter of you saying that balance demands perfection when it doesn't and never has.
Kind of like how D&D classes are different and have unique strengths and weaknesses. Unlike Starcraft of course, D&D is a team game and not a competition so it's also comparing apples to oranges.