The missing symmetry in your own analogy is that Cryptocurrencies themselves are protocols with their own inherent (if not requisite) platform problems.

In theory, protocols like the blockchain are open, decentralized, interoperable. Yet in current practice a cryptocurrency only works with platform lock in: if you don't lock people into your platform it isn't monetizable. Market forces push toward closed (artificial scarcity, rising costs for new players to enter the market versus entrenched players/miners/etc) and centralized (central wallets/brokers/exchanges on the one side, complex miner unions as complex political boundaries form on the other side).

I'm not sure cryptocurrencies can save the internet from platform problems when they themselves are platforms.