I even go back to stuff like game gear with its dual switch mode supplies (buck/boost), the 32X (buck….okay maybe 32X isn’t a great example) and then the various switch mode power warts that shipped with the consoles before then. Given the PCB cost constraints of the day, they weren’t even properly constraining the loop area of the high current loops and likely leaning on the large value caps to sink the high frequency transients as well as inductors between the voltage rails and regulator output. I’ve been spending a lot of time over the past year designing and laying out switch mode converters and load testing them to characterize their noise/ripple. The only one I had that exhibited egregious high frequency noise was when I routed the return path for the output incorrectly, which caused this horrorshow, which shouldn’t be hooked up to anything you care about 🤡