if you have less data you buy older generation tapes, LTO-5 is 1.5 TB uncompressed and should be in price sweet spot right now.
Maybe. For the average person here though they will already have and want a blu-ray drive for "reasons", and so using it for backup is very cheap. LTO-5 might be cheap, but they still need to buy a drive that they won't use for anything else.
If you are a business of course tape is cheap. Even then, a few usb harddrives are cheap as well and much faster.
You have to take into account that there aren't (or very few usb) LTO-5 enclosures. While you can potentially find an LTO-5 drive >$200 these days, you also need an equipment with SAS or 8GB FC interface to be able to use it.