I will never sell ETH to buy Solana, I prefer to hold ETH over Solana, although at the moment Solana looks convincing but I am sure that ETH will skyrocket again soon and the opportunity to become the king of cryptocurrencies replaces bitcoin.
Solana is young and it is in phase of Ethereum a few years back. It is on hype but we need more years or at least the coming bear market after this bull run, to see how their developers will keep working for products, upgrades and how their ecosystem will maintain and grow up. Bad market will give really strong projects to shine. I hope Solana will be one of such projects next 2 to 3 years.
Holding ETH is not wrong and is still in a very good category for anyone, but if you expect ETH to become the king of cryptocurrencies and replace Bitcoin, it is a dream that will be very difficult to come true because when Bitcoin started to fall in the market, ETH was still experienced the same thing, meaning that ETH still often follows the cycle of Bitcoin conditions to date, so there is very little chance of becoming king in cryptocurrency.
ETH is one of best cryptocurrencies and if anyone ask me to pick a few cryptocurrencies which I consider as asset of storage, I will pick Bitcoin, Ethereum, BNB first. Other altcoins will need years to become asset of storage like these three coins.
Solana, Polkadot are promising altcoins in last 2 years but they have to be tested more.