They might be. All of this can be weighed by judges.
I'd be inclined to say: sorry, licensing/selling to companies not in the market is now not possible.
If you need to mitigate risk, insurance companies (etc.) can offer products against patents -- they still have value, just only now to companies actually operating in the relevant market.
And of course, "relevant market" can be read broadly by judges.
Either way, patent law is running amok over innovation, and goverment shake downs and money transfers from producers to rentseekers is a net loss for everyone.
But by licensing the patent to interested parties, they might be supporting R&D of people who might not otherwise be doing R&D in this direction.
The ability to license some tech you know is likely to work in the form of a patent has some value.