We got totally thrashed in our FJ Cruiser 2 weeks ago when the leader took us on an ATV trail, way too narrow, with thorn bushes on both sides. We too had white streaks really bad!!!!! We have the bright yellow color and the pinstripes were completely from end to end, top to bottom of the sides of car, and really noticeable in this color. We just wanted to knock them down a bit, never going to remove them completely.
I used:
1) Meguiars Medium Cut Cleaner - applied with orbital buffer. I did this 3 times. It has diminishing abrasives so you can't sand off your paint!

2) Then I used Meguiars Scratch-X with the orbital buffer. Did that 2 times

3) Then used ICE car polish. Applied by hand. Removed with microfiber cloth.

4) Then used synthetic wool bonnet dry to just buff it a bit and remove smears from the ICE which is like an oil.

5)The black plastic B pillars were BADDDDDDD!!!!!!......, I used Meguiars Plastic-X with the orbital buffer, applied a bit of pressure. They look like NEW, completely removed scratches, nice and smooth. Obviously plastic is softer than paint so it could remove them.

Now, on the paint, you can only see them at an angle in the sun, no more white streaks. We were satisfied.