1.ETH is the native currency in the Ethereum Economy. Ethereum is similar to an emerging economy.
If you want to participate in many activities in China, you need RMB.
If you want to participate in many activities in Ethereum, you need ETH.
For example, to participate in ICO Boom in 2017 on Ethereum, you need ETH.
to participate in DeFi Summer & NFT Boom in 2020/2021 on Ethereum, you need ETH.
to participate in little restaking Boom in 2024 on Ethereum, you need ETH.
So ETH is clearly a currency, similar to USD, China Yuan, Japan Yen...
2. Can you be more specific what made Ethereum not decentralized? Which big boys controlled ETH?