People don't really understand that ETH 2.0 is a multi-year update with several phases of implementation.
It starts with phase 0 and it ends with phase 2.
So far phase 0 has been delayed multiple times and is not designed to provide scalability through sharding, it is designed to implement a Proof of Stake sidechain (called the Beacon Chain)
and it will focus on setting up Proof of Stake validators. This will not fix Ethereum network congestion or its associated high gas fees. And it most certainly not fix the much much higher fees
that people get when interacting with the DeFi protocols (fees up to $100). Thereby trapping people within DeFi token projects.
Only phase 1 & 2 will focus on implementing a scaling solution through sharding and those phases are still years away.
Link :
https://consensys.net/knowledge-base/ethereum-2/faq/Ethereum 2.0 is planned to be rolled out in at least three phases: Phase 0, 1, and 2. Phase 0 is planned to launch in 2020, with Phases 1 and 2 to be released in following years.
Phase 0: In the first phase of Ethereum 2.0, the “Beacon Chain” will be implemented. The Beacon Chain stores and manages the registry of validators, and will implement the Proof of Stake (PoS) consensus mechanism for Ethereum 2.0. The original Ethereum PoW chain will continue to run alongside the new Ethereum PoS chain, ensuring there is no break in data continuity.
Phase 1: The second phase of Ethereum 2.0 will likely roll out in 2021. The primary improvement of Phase 1 is the integration of shard chains. Shard chains are a scalability mechanism in which the Ethereum blockchain is “split” into 64 different chains, which allows for parallel transaction, storing, processing of information. At its most conservative estimate it will enable 64 times more throughput than Ethereum 1.0, but it is designed to be able to handle several hundred times more data than Ethereum 1.0.
Phase 2: The third phase of Ethereum 2.0 will likely be launched in 2021 or 2022. This phase is currently less clearly defined than the above two phases, but will involve adding ether accounts and enabling transfers and withdrawals, implementing cross-shard transfers and contract calls, building execution environments so that scalable applications can be built on top of Ethereum 2.0, and bringing the Ethereum 1.0 chain into Ethereum 2.0 so that Proof of Work can finally be turned off.
Many further improvements are planned for research and development after Phase 2 is complete. Vitalik provides insight into some of these improvements in this easy-to-digest diagram.
There are some ad hoc solutions (solutions designed for a specific problem or task, non-generalizable, and not intended to be able to be adapted to other purposes) getting developed to address the high fees,
but these ad hoc solutions will not be available to all users. Most likely only a select few token projects will implement them.
So to summarize : ETH 2.0
phase 0 is not the solution of high gas fees.