I just did a search on changing brake fluid. Would link to the site, but I do not know how. At any rate, it says there’s no mention in the service manual of changing brake fluid on GM and Ford vehicles. Maybe that’s where the urban legend comes from. Most of my vehicles have been domestic. I guess that’s why 30k seems early. I didn’t see Toyota’s recommendations listed.
The site does advise to change it, though.
AA1car.com “why change brake fluid”. Hopefully that isn’t considered spam. Didn’t notice if they were trying to sell anything.