It's your truck. The rear plate is pretty flimsy, but it would offer at least a little protection for your oil pan. If you don't off-road, though, then you could probably survive without it. Why do you want to remove it, though? Is it in your way? The grill doesn't do much either, but people leave that on.
I took mine off after the 1st oil change because it's in the way and never put it back on (of course now I have aftermarket skids). The stock one doesn't protect much, especially if you don't off road. I took it off my Taco too.
Hows it in the way for oil change, there is a hole for the bolt.