The shift from PoW to PoS has significantly reduced Web3's environmental impact, addressing much of the eco-controversy. PoW's energy-intensive mining, as seen in Bitcoin, consumed vast electricity, drawing criticism. PoS, adopted by Ethereum, slashes energy use by over 99%, relying on staking rather than computational power. However, debates persist: PoS critics highlight validator centralization risks and residual hardware energy costs. Meanwhile, layer-2 solutions and emerging eco-friendly blockchains further mitigate concerns. While PoS isn't a complete fix—data centers and node operations still consume energy—the transition markedly improves Web3's sustainability, though ongoing optimization and renewable energy adoption are crucial for fully resolving environmental critiques.