If you think these defi projects are hurting the environment then you have not been paying attention to the industry. Proof of Stake, what most smart contract tokens are moving to, is very energy efficient.
Is anyone actually really sure that Proof of Steak is secure though?
Anyway, none of this matters because Bitcoin exists and is the dominant shitcoin (due to first mover advantage). All these other shitcoins can claim whatever efficiency, but it doesn't matter because that's a very isolated view of the problem. The shitcoin economy as a whole will still be fueled by mining unless somehow Bitcoin gets dethroned and the whole mining thing just goes away. I can't imagine that happening without the whole economy crashing completely into the ground – but that would bring all these efficient coins down with it.
Yes, they've been live for years. Bitcoin can't do smart contracts, it's not a Turing complete scripting language and it's very difficult to work with, so of course it matters.
