Worth noting that things like emissions from hot metal and (though you didn't mention it) keeping the air path away from things like circuit boards or plastics

Worth noting that things like emissions from hot metal and (though you didn't mention it) keeping the air path away from things like circuit boards or plastics are considerations and even marketing points for high-quality cannabis vaporizers. Some use ceramic heating elements instead of metal for this reason as well. Edit: also worth noting that cheap no-name ones are frequently soldering iron elements housed in random plastic or wood cases and have no consideration for this whatsoever.