Unfortunately the screenshot didn't take, but I just had two planes each generating over 20k/second in scrap metal. Total production was something like 60k.
It's kind of out of hand in FS games. I've got every trader goodie except Ion Cannons on two planets, a nearly full spire fleet (don't have the research for dreadnaughts yet), and every mercenary ship built. I have 9 million metal I literally cannot spend.
The nice thinga bout this is that I was able to do it in well under half the time it took to do it the last time I tried to build something this crazy. So it definitely speeds things up, but when an exo breaks on a spire city, the 32% scrap I'm getting translates into "rush build a planetary armor booster in 2 minutes".
So I guess this is more of an observation than anything else. I'm not sure if anything should be done about it or not. Just noting that if you can build a solid chokepoint, the sheer amount of resources you get out of it will let you build stuff crazy fast.