Note that internal HDDs aren't taxed under this tax, only external ones. (So if you don't want to pay it, you can just buy a SATA HDd and an adaptor). Phones are taxed though (yes this doesn't make any sense technically)

Is the tax on a phone's storage capacity or its overall retail price?

On the storage capacity

We have that in Italy too, but at least that means that ripping CDs or DVDs is entirely legal. It's actually called private copy contribution.

Yep it actually came from Germany, and was afterward adopted by a lot of european countries

Germany has that too. Even on paper, since you could copy pages under copyright.

Honestly, I'd take that trade. A narrow, stupid tax is definitely the lesser of two evils here. (Especially as it means I'd have a moral license to pirate whatever I wish!)