> You cannot use any of these crypto tokens as a form of fast payment
Compared to what? Sending funds to residents of some parts of the world might be frustrating as hell if using not crypto.
> without scams
Consider to learn something about an idea of trustless.
> without damaging the planet
Consider to find a good use of extra heat if you are mining.
> without the huge volatility
Let me guess - your country is not being invaded by enemy soldiers and its currency is not being in free fall.
> and speculation
Thanks Satoshi I do not need to ask some authorities about what to buy and when to sell it.
> without it also being used on the dark net.
You have chosen a wrong goal to follow, dark net does not mean dark ages.
> There is no real world legal use-case and it is a complete scam.
So, maybe you're living not in real world? In a world where everybody from governments is always fair? And evil Satoshi Nakamoto steals your money/coins/soberness?