Not saying that the guy was right, but you realize that citing the number if IBUs doesn't prove him wrong, right?
There are literally dozens of reasons that dismissing such a comment because it's 55IBUs may not be wise (eg stylistic reasons, or not actual getting 55IBUs that is ESTIMATED), but by far the biggest reason why it's pretty bogus "proof" of him being wrong is that saying you need more hops generally refers to hops used to contribute actual flavor/aroma, which makes citing the IBUs entirely irrelevant.
Not saying it was necessarily the case, or that this judge was in any way right, but people in general are very often all-too-eager to justify in any way possible (regardless of validity) entirely dismissing a poor score/critical comments, when these are frequently the most important and scoresheets a homebrewer can receive.