The core idea behind “new state types” is to stop treating all state as equal. Some initial ideas: 1. Hot-cold state separation See EIP-8188/8295/8296. The core idea is to price cold state storage significantly higher than hot state. This would enable clients to implement hot-cold database separation, improving overall state performance. Historical analysis shows that retaining roughly 3% of the state in hot storage accounts for ~94% of all updates (on a monthly basis). 2. Temporary state A new state category that is automatically pruned after a defined time period. About 55% of state slots are written once and never accessed again, so applications can make use of this feature if emphemeral slots fit their use cases (main incentive is cheaper gas). 3. Trieless contracts Replace the contract trie with some fixed size cryptographic accumulator. Not all applications require state proofs. The state hasn't been improved since genesis. So it's about time.