Wow. Glad I ran across this thread.
I have a 2017 Off Road with less than 900 miles. It has similar streaks when the windshield is wet but not nearly as bad.

Now I know I need some windshield polish!

I use CLR, calcium-lime-rust remover. Cleans all of the crap off the windshield.

I have the same problem with my windshield. In the morning when there is condensation I have numbers that appear on the left side by my registration sticker and circles on the glass that appear that must be when the windshield was installed on the assembly line. Not only is it very annoying but it is also very dangerous. I have never had this issue on any other vehicle that I have owned. Bought my 4Runner in August and have had this issue since day one. I wash by hand never carwash (so far). I just ordered some Glass Polish to see if it will do the trick. I am also going to change wiper blades to Bosch.

Hey everyone, even though I just traded in my very nice 2018 Off Road Premium after only eight months I felt the need to pop back over here and let you know how I solved an issue that made me a bit insane for a couple of weeks.

I also had these mystery streaks on the glass when it was raining (as well as the ghost of some stock number that Toyota must have used on the glass). You would see these streaks just after the wiper pass and then they would kind of disappear. The thing is it would make it very hard to drive in the rain. You wouldn't see the marks at all in the dry. It was like they were magic.

I tried a bunch of stuff to remove them: A half dozen brands of window cleaner. Different brands of paper towels. Newspaper on vinegar. A razor blade. Different brands of micro-fiber towels. Glasweld window polish (Do NOT use, it looked like it was working but when you looked at it under a bright light it was leaving micro-scratches that were causing a haze). Anyway, Griots Garage FINE Glass polish on a micro-fiber towel rubbed on and buffed by hand removed it permanently without a haze. It took some time but it was worth it.

Note: Clean the crap out of the window first and switch out the NEW micro-fiber towels a couple of times as you go as you don't want to pick up something and scratch your windshield. And that first evening you might freak out like I did when you see a bunch of little 2mm marks when looking through the windshield at a streetlight. It looks like you scratched the crap out of the glass but they are little fibers from the micro-fiber towel and they will wash off.

And as for why I traded-in what is a perfect example arguably the most reliable vehicle on road? I got rid of my 3rd Gen to get a new 5th Gen and I found the extra foot of length and the extra eight inches of width annoyingly large when driving in the city and buzzing around in tight traffic on the highway. Likewise, I found the smooth, quiet ride a bit too isolating and I found that I like to feel like I'm actually driving. Still, if I had to have one crazy-reliable vehicle for the apocalypse, the Runner would be it. Whoever buys my truck of the lot is going to get a great one as it was completely rattle-free, never eaten in, never off road, no one ever in the backseats, no pets. It is better than new as it has been gently broken in and polished by hand a number of times.

Good luck to all and thanks!

Thanks for the tip. I need to give tat Griots stuff a try. I recently went trough a few touchless washes and the streaking is awful. Sorry to see you go... Maybe you'll be back some day. You never know when the Zombie Apocalypse will happen...