I never was a fan of the semicolon. Honestly, for most of my life I had no clear understanding of its usage. It wasn't until I graduated college, had switched careers a couple of times and ended up an English teacher that I finally really figured out the whole point of the semicolon*. I honestly don't even bother with the semicolon in my classroom. Personally, I'd rather read something without any semicolons at all instead of a paper that reads like the kid just randomly spliced sentences together with this accursed mark because they're trying to put what they learned to use, especially when there's no actual use for the mark. It's really the only punctuation mark where proper usage is entirely a matter of subtlety and perception, and as such isn't something the typical high school kid is going to grasp with their begrudging effort master the subject. Sure the comma, with many of its "either way is really correct" usages, can get a little confusing, but it's not the c of the punctuation set either, redundantly doing the work other punctuation marks do just as well.
For a more interesting on the history of the semicolon, try this surprisingly readable Slate.com piece.
* This is also how I fully grasped the correct usage of the word whom. This wasn't a point I made a ton of mistakes with before, but it wasn't something where I understood the usage either. I'm now able to explain its usage pretty clearly, although I'd much rather hear a person who's forgotten that the word whom exists than someone who uses whom in inappropriate places. There's nothing worse when it comes to language than hypercorrection in my opinion.