12-tone serial composition is simply a technique for removing natural tonality from a composition.
I think the big issue is whether 12-tone approaches are used occasionally in a piece as an expressive tool, or as a "new way of life" where the entire composition is serial, and the listener is stuck in it. Or all of a composer's work is serial.
Which is what makes it... challenging.
It's the same with Minimalism.
But used in smaller doses, it's a powerful technique.
Here's an example, in Frank Zappa's "Brown Shoes Don't Make It" there's a little section that's a 12-tone piece, starting with the lyrics "We see in the back of the City Hall mind...". It's short, it's weird, and it works very well in context.
And in Zappa's "St. Alphonso's Pancake Breakfast", the middle instrumental section, the first 20 notes are going up and down a simple C-Major scale... (What could be more tonal?)... and then he rips into a 12-tone row. The result is downright delightful.