People are generally careless unless someone either specifically points out or legally mandates and monitors the risk. I can remember when people were calling asbestos harmless, and even have a neighbor who was once a pipeline painter, ended up for two years in the hospital at the age of 50, and could never work since, because anyone who wore respiratory filtration was called a sissie back then. Gosh knows how many "artistes" I seen become terribly ill over the years. But yeah, there is profound difference between something like metol, which might lead to skin rash, and something like chromium salts, often used in alt processes. The hazards of "pyro" are pretty well known industrially, so it doesn't surprise me at all that certain photographers might have gotten messed up by it back in the naive pre-glove days. Nuclear fallout was considered innocuous at one time too. I happen to sell tremendous amounts of EPA-certified cleanup equipment to certain trades. A lot of this is legally mandated these days, and there are always a few macho boneheads objecting to it, or trying to form
a lobby to get the rules shut down. Those types either don't live long, or lose everything resembling a quality life, health wise, or end up
ruining someone else's health, possibly their own wife or children. I've seen it over and over and over. Better safe than sorry.