Yes. The recruiters who troll LinkedIn must just search for one specific skill and spam everyone who has it. I always get offers for jobs I'm either not qualified for or would never willingly do.
Last year I realized that I'd never changed my LinkedIn job profile info to "not interested" after starting my new job a year earlier. I'd been getting a lot of pings from recruiters, and I thought that might discourage them. Nope. Saying I wasn't interested made the recruiters even more interested in me!
Which would be great if any of them had a job better than my current one, but they never do. Everything is more boring work I'm less qualified for, for less pay.
When stuff falls into a black hole, it gets measurably heavier. If a charged particle falls into one, the black hole retains a measurable electric field. If a black hole picks up angular momentum from gas circling in sideways, the hole spins faster, and the gas fired from the jets comes out at a higher speed.
Your argument that mass or energy exists that isn't measurable since it isn't observable sounds a little illogical... how would you even know there was such a thing if nobody had measured it for you in the first place?
Actually Stephen Hawking would have agreed with you in 1997, but by 2004 he decided he had lost the bet with John Preskill of Caltech.
"Pay no attention to the man behind the curtain." -- Karl, as he stepped behind the computer to reboot it, during a FAT