It's just a somewhat poetic way to describe the flavors you get when cooking with really high heat really fast. You can't get it on teflon because you're using temps 100+ degrees above what teflon can handle without decomposing.
That being said, you don't need to be using gas. It is possible to get good wok hei on an induction wok, despite what the foodie peanut gallery says. Not on a 120V unit, though. You need to use a commercial multi-kilowatt setup.
The risks of ceramic coatings less so, but still concerning: https://foodpackagingforum.org/news/nanoparticles-released-b...
Either way, neither is safe for higher heat cooking. At the very least, ceramics will rapidly degrade if used for such.
In fact if you have birds, it’s best to not have teflon at all, because they are so sensitive to teflon fume poisoning: https://beaknwings.org/wp-content/uploads/2021/07/Teflon-Tox...