Charles Hoskinson, co-founder of Ethereum and founder of Cardano, has publicly expressed his opinion that Ethereum may not last more than 10 to 15 years. His reasons are based on a series of structural problems in the protocol, such as an inefficient accounting model, an obsolete virtual machine, and a consensus system that is not long-term resilient.

Reasons for the prediction:

Inefficient accounting model:

Hoskinson argues that the current model of Ethereum is inefficient and introduces unnecessary frictions in the ecosystem.

Obsolete virtual machine:

The Ethereum Virtual Machine (EVM), which is the execution engine for smart contracts on Ethereum, is considered obsolete by Hoskinson.

PoS consensus system:

Hoskinson questions the effectiveness of Proof of Stake (PoS), Ethereum's consensus system, for long-term scalability and decentralization.

Scalability issues:

Ethereum's Layer 2 (L2) solutions, designed to scale the network, are seen by Hoskinson as a temporary fix that does not address the fundamental issues of the main chain.

In summary: Hoskinson believes that these structural problems will make Ethereum unviable in the long run, and that it could disappear in the next 10 to 15 years.