Again, anyone actually familiar with Gothic studies (I trained in the field and remain employed in a closely related one) would know that people didn't outright "go against Jordanes", but rather the Gothic Urheimat was always discussed as a matter of controversy, with Jordanes' claims one version but external evidence lacking. Now there is some external evidence.

Historians hold out on claims made in historical sources -- especially when written centuries after the fact -- all the time, it is a standard scientific practice to seek external evidence.

And for having worked in a similarly behaving field, there is a big difference between “yeah we're not sure yet” and “no the ancients are most certainly wrong because our Modern Thinking is necessarily better (wink wink)”.