Bitcoin was not designed as a state machine, but as a way to store transactions which can be used to construct a state machine offchain.<p>Ethereum tries to implement a fully self contained state machine in its system. This is where all its problems come from.<p>Because every Ethereum miner has to validate every transaction in the entire network, a Proof of Work model is too inefficient for them so they have to transition to Proof of Stake (Whether this will succeed or not, or whether it will even launch or not, is outside of this topic). This is also why Ethereum transaction fees are so high nowadays.<p>Also because the main design goal of Ethereum was to make a "Turing complete blockchain" (which it technically isn't), it had to add a new concept called "gas", which adds an additional layer of complexity (compared to bitcoin). This gas concept has resulted in all kinds of UX challenges.<p>Bitcoin has its own flaws too. Most Bitcoin investors no longer believe Bitcoin was meant to be used for transactions, but just as a way to store value, like digital gold. So there's not much you can do with it other than speculative investment, hoping that the price will skyrocket at some point. Basically, it's not really interesting for most hackers, it's become a wall street toy.
Bitcoin vs Ethereum<p>premine: 0% vs 70%<p>reward schedule: set in stone vs subject to change<p>philosophy: immutable vs experimental<p>blocktime: 10 min vs 13 sec<p>balances: utxo-based (unspent transaction output) vs account-based<p>scripting: branchless programs vs stateful & Turing complete<p>complexity: low vs high