"an activity involving physical exertion and skill in which an individual or team competes against another or others for entertainment." Is the definition of a sport. Cheerleaders work hard and work out each practice to be able to stunt and do tumbling. And in competitive cheer, you are competing against other teams for the prize! So why on earth is cheer leading not considered a sport?

I consider it more of an art form, similar to ballet, that requires great physical ability and practice, but is not actually a sport, like football or basketball.

Cheerleading is considered a sport, just not a competitive sport. They have cheer competitions, but most sports consider to have an objective. Cheerleading doesn't really have an objective. You get a prize in the end if you win, but it isn't really an objective. For example, you are trying to get a touchdown in football. In soccer, trying to score the goal. In baseball, getting around the bases for points. In cheer, there isn't as many times to get points. It is one routine, then you get the points. Cheerleading is a sport, just not a competitive sport.

It was considered a sport on the 31st of May of this year. Anyone who actually cares about the topic should have dropped it then.

Some people consider it a sport, others not. It is subjective so neither position can be proved. Only debate this if you enjoy debating.

It's not competitive and isn't easily judged on technical merit. Plus it was designed to help teams to generate atmosphere so it has always been something which aids sport and not a sport in its own right.

Mainly because most people don't find it entertaining

because it's for gymnastics wannabes.