I can tell you that my 1996 Rav4 doesn't need to be inspected this year or hereafter. Possibly, that's why I currently have a check engine light for Code P0401, the Vacuum Switching Valve has gone bad in the smog control system. I have the parts to fix it when I get around to it, but I'll still get my tag renewed next month with no problem.
Gee, I'm glad I don't live in California anymore. It's hard to believe it's been forty six years now. Sitting with my beautiful wife on bean bag chairs in front of the TV watching the Tall Ships in the harbor. It was magical back then.
I never paid attention to the color of the stickers except there was a new color for each new year.
The eagle eyed car people know the ages of our vehicles and apparently when we get the vehicles smogged and a new sticker color. That alerts those looking for older and still smog passing vehicles.
No one in my family really knew about this clue re buying a used vehicle in California.