[VLM]

Actually thats the junction temp so unless you have an infinitely thermally efficient package and heatsink, if you're boiling water the innards are way out of spec.

Also check out the temperature derating curves.

That series has a thermal shutdown ckt so "operating nominally" above boiling pt is kind of hard to define.

There are also non-regulator thermal issues, like most cases are not designed to operate continually at 125C internal temps, and the electrolytic caps nearby the reg have their lifetimes drop with some polynomial of temp above room temp so smoking hot reg isn't good for everything nearby even if isolated by itself it would be OK.

Finally the general idea is still true, that you can get a nice 2nd degree burn or think something is "really hot" at a temp well below rated.

There are plenty of high power transistors rated to 150C junction temp. Not impossible with a really good package and heatsink (low thermal resistance) and good assembly technique to be able to boil water on one of those. As a stunt in the lab everyone tries this sooner or later to see if their anti-thermal runaway ckt is good enough and their assembly technique is good enough.