Language changes. The meanings of words change. Their usage changes. And English is a particularly stupid language already, so I always roll my eyes when I see posts like this.
Roll with it. Heck, come up with a few changes of your own so you spend less time infuriated with what others say. If you know they mean systemic when they say systematic, and so does everyone else, the purpose of the word has been served.
I refuse to categorize improper usage as a trend or evolution. It's simply incorrect. That's exactly how we end up with English dictionaries giving up the struggle and including non-words like irregardless.
That's my story and I'm sticking to it.
*MySmiley*
"Bustin' makes me feel good!"
Ghostbusters, by Ray Parker Jr.