That's interesting, especially given that I don't ever recall seeing such admonitions on the outside of the packaging. Maybe I need to pay more attention.
My experience with lighting is varied. I know I have at least two LED bulbs which specifically advised they were for indoor use only, which I went ahead and used outside and, as of this writing, they are still working some 5-6 years later. I also have a few spiral CFLs in table lamps that are still working; those things must be a dozen years old (at least).
What's really hilarious

is that our kitchen has six recessed spot/flood fixtures in the ceiling, all of which have incandescent bulbs in them. Probably seven or eight years ago, I bought a case of LED spot/flood replacements to swap out as the old incandescent bulbs croaked off. Not a one of those effers has died, and they, as you can imagine, get a lot of use. They were on a dimmer circuit, but I took that out just a few months ago, anticipating a few failures. Still nothing...they will live forever.