It's not that bad, though. The Ethereum chain is about 1.4TB right now.[1] Growth is roughly linear. Bitcoin is under half a terabyte. Those are manageable numbers given current disk sizes.
The size of the Solana blockchain is claimed to be only 10MB. That's tiny. Where is the data stored?
From the article: "Parts of this article were generated with the assistance from AI tools and reviewed by our editorial team to ensure accuracy and adherence to our standards." Right. That's Coinbase trolling for clicks.
[1] https://ycharts.com/indicators/ethereum_chain_full_sync_data...
It's not deleted in the sense that all of its history is still on the blockchain. But it is deleted in the sense that the account storing the Solana program no longer exists / is empty and you cannot interact with it. In fact, if you haven't immutably deployed a Solana program, you are heavily incentivized to delete it if it is unused, because then you can recoup the Solana you posted as rent to upload the program in the first place.
Think about it this way: 99% of these protocols are DeFi related. In all of those protocols, you ultimately have makers and takers, regardless of whether the protocol is literally an orderbook or an AMM (automated market maker) or something else entirely. The point is, you have two sides: someone making and someone taking. But blockchains, even the fastest ones, are still multiple orders of magnitude slower than TradFi. We're talking milliseconds vs nanoseconds. Remember, there's three orders of magnitude of microseconds between the two also. Anyways, it's basically impossible to update your quotes fast enough as a market maker on a blockchain to not get picked off. It's hard enough to do this in TradFi nanosecond land, let alone on chain. Yes, there are differences. Yes, it's nuanced. But market making on chain is fundamentally very hard and 99.9% of people who try, fail, or they "succeed" but eventually realize they would've made more by just bagholding the collateral they posted to make markets. So the liquidity (market makers) in all of these protocols eventually dries up. At which point the protocol is useless because no taker can come and trade. At which point the protocol is abandoned. At which point, if deployed immutably (this is the only truly trustless way), there's nothing you can do. If NOT deployed immutably, you can just close the program and recoup the money, could be thousands of dollars, you posted as rent to upload it in the first place.