How is Ethereum 2.0 different?

Compared with 1.0, 2.0 mainly introduces two improvements: PoS (Proof of Stake) and Shard Chains.
For miners, the biggest difference between Ethereum 2.0 and Ethereum 1.0 is that it will use the "Proof of Stake (PoS)" mechanism to replace the current "Proof of Work (PoW)" mechanism.
To illustrate: Imagine that Ethereum 1.0 is a busy road with only one lane in each direction, which means that in times of congestion, all vehicles have to crawl through at a slow speed.
Ethereum 2.0 will introduce sharding, with the effect of turning the blockchain into a highway with dozens of lanes, all of which will increase the number of transactions that can be processed concurrently.
The impact of Ethereum 2.0 on existing miners
Some people are happy and others are worried. The conversion of Ethereum to PoS means that the income of PoW miners will gradually decrease until they cannot obtain income.
You should know that the launch of Ethereum 2.0 must reach at least the 1.5 stage, and it will take about two years to wait during this period, and it will take longer to fully switch to PoS after launch, so there is no need to worry too much.
First of all, we know that ETH 1 is the PoW chain that miners have been participating in, and ETH 2 is the Ethereum 2.0 of the PoS consensus. After the merger of ETH 1 and ETH 2, the PoW mining of ETH 1 will stop, and the consensus upgrade of the entire Ethereum network will be completed.
The expected time for the merger of the two chains to occur is at stage 1.5.
At that time, it will enter the phase 0 of the main network, but limited to the development process, any economic activities of Ethereum will still run on ETH 1, and the underlying consensus will still rely entirely on PoW mining decisions.
To completely change from ETH 1 to ETH 2, it is necessary to complete the blockchain witness mechanism, modify the current Ethereum virtual machine, and change the data structure from hexadecimal to binary. It is equivalent to changing from a consensus bottom layer to one of the shards closer to the user layer. The workload is by no means as simple as we imagined.
The interests and positions of all parties involved in this, in addition to the consideration of miners' mining income, a more practical question is whether the code of ETH 2 can Safe enough to undertake? The transition of wallets, exchanges, stablecoins, and many infrastructures will take more time.
Before all this happens, Ethereum still needs PoW mining to support the good operation of this system.