I can't say, beyond a shadow of a doubt, that I have seen people use the word guarantee either. That is beside the point though.
It is beside the point, because I HAVE seen, people say in answer to the question of "what would make Madden better", and them answer competition. I HAVE seen people say that lack of competition is THE biggest reason why they think Madden is not a good game. I HAVE seen people say that the only way to have a good Madden, is to bring back competition. How else can you take those statements, other than to mean that they think that if there was competition, that Madden would magically be better? They don't have to specifically use the word guarantee. Their position could not be clearer, even if they did.
And there is nothing wrong with optimism, but there is also nothing wrong with cautioning against, or tempering enthusiasm, to a realistic level. And if anyone's optimism includes thinking that all Madden needs is comp, then yes, that is an unrealistic expectation. Competition MAY help, but it very well MAY NOT. Not saying anything more than that.
It's fine to give the other POV, but on this one single statement, "competition does not guarantee a better Madden", there is no other POV. That is a statement of fact and should be treated as such. Facts don't have POVs. Opinions do. If you think that there is another POV to that statement, then that adds more credence to my belief that this is a misunderstanding.
But it should not be an argument.