I have trouble with using the terms subjective/objective to determine whether something is a sport. No sport is completely objective. There have been plenty of basketball/football games where the outcome was determined by a ref's subjective interpretation of a rule.
Additionally, I would argue that no, the winner in a boxing match is often not clear by the end, and you end up with some outcomes decided by judges that are hotly disputed. By the objective/subjective definition boxing would only be a sport if one of the boxer's KO"d the other.
Also, the sports that are considered "subjective" are, in fact, not as subjective as many would think. For instance, in gymnastics there are specific elements with predetermined point values. The judges are only allowed to deduct specific amounts (they have a very small amount of leeway) for specific things. I'm not suggesting these sports (gyimnastics, ice skating, etc.) don't have more subjectivity to them than the average basketball game; I am just saying that no sport is completely objective and these sports aren't as subjective as some believe them to be. It isn't as if some judge looks at a beam routine and says, "Well, I liked that pretty well. I think I'll give it a 9.6 (old scoring system)"
Objective versus subjective just isn't a great working definition because you would have to argue how objective does it have to be in order to be considered a sport or how subjective to not be considered one. If the presence of judges determining a winner is the standard then boxing is not always a sport and other traditional sports aren't sports if a ref's interpretation of a rule determines a winner because a referee is then making a judgement call that determines the outcome between two opponents.
The technical definition of a sport is a physical activity that is governed by a set of rules and often engaged in competitively. That's a very broad definition, and I'm sure it still leaves a lot of this up for debate that isn't going to be settled anytime soon.
In the meantime, the judge never said that competitive cheer wasn't a sport. What he actually said was that as THIS particular school was running it - the competitive cheer program did not meet the NCAA guidelines that would keep the school in compliance with Title IX requirements and therefore it didn't meet the definition of a sport. Basically, the school was trying to make a cheap end run around Title IX, and the judge called them on it.
Finally, the particular type of "competitive cheer" program that Maryland, University of Oregon, Baylor and a couple of other schools run is not the same thing that University of Kentucky does. There are similarities, but the requirements and scoring are different. It is more typically referred to as "team stunts and gymnastics".
Here's a great link that explains the differences between cheer (on the sidelines), competitive cheer, and team stunts and gymnastics as well as a good explanation of the ruling and how it might effect other schools with similar programs.
http://www.registerguard.com/csp/cms/sites/web/news/cityregion/25051434-41/competitive-cheer-team-oregon-ruling.csp