Yes, it is pretty sad state of affairs that there are so many fakes out there. I've never seen an etched diamond Telefunken fake. I read somewhere that there are now even molded diamond fakes. I know that my 803S tubes are not fakes (bought before fakes became a thing) because of their age and because the crumbling boxes would be a really tricky thing to fabricate.
Cosmetically, some fakes are quite impressive. I've seen Western Electric transformers which have appropriately aged decals, fake rust, etc. that made them almost indistinguishable from real. The fake Audio Note interconnects that I've seen were pretty easy to spot if you compare them to the real deal, but, I would not have spotted the difference without comparison to the real deal.
Cosmetically, some fakes are quite impressive. I've seen Western Electric transformers which have appropriately aged decals, fake rust, etc. that made them almost indistinguishable from real. The fake Audio Note interconnects that I've seen were pretty easy to spot if you compare them to the real deal, but, I would not have spotted the difference without comparison to the real deal.