Dull, matte tailpipe is very visible (due to high ground clearance) and looks like crap in the context of a shiny FJ.
Solution:
...and a whole lot of rubbing.
The stock pipe now looks great! Shiny, but not mirrored. The look matches the fake aluminum bumper trim.
A temporizing measure until my exhaust tip comes in the mail... but I like it so much, I may keep it this way.