1) Nodes don't get rewards from Mining

This is the biggest flaw that I can imagine. It was a basic assumption of satoshi that mining will remain decentralized since he assumed that 1 miner will be 1 node, and everyone will mine on his PC with the CPU. However the SHA mining alhorithm is not ASIC resistant and when ASICs became widespread, mining was centralized. This is not particularly bad because mining will either way get more efficient.

What is bad is that the nodes are not incentivized, and as mining is centralized. So that only the miners will be nodes in the future and hardly anyone will run a full node. Now because of this we cannot hardfork because the node count will shrink more and more. This really fucked up the entire bitcoin system, how can such fatal flaw not be obvious to satoshi?

“There are only as many nodes on the Bitcoin network as there is demand to perform independent and trustless validation of transactions.”

The node count is a function of the demand for trustless transaction validation versus the cost of running a node. As such, I’d posit that node count is also dependent upon the value being stored and transacted by bitcoin users.

While some claim that running a node today is purely altruistic, there are incentives for doing so:

Investment: If you’re highly invested in bitcoin, you may wish to support the network in order to protect that investment.
    
Performance: It is orders of magnitude faster to query a local copy of the blockchain as opposed to querying blockchain data services over the Internet.
    
Permissionlessness and censorship resistance: By receiving and sending transactions from your own node, no one has the power to stop you from doing so.
    
Privacy: If you’re querying other nodes or services about blockchain data, they can use those queries to try to deanonymize you.
    
Trustlessness: Owning a copy of the ledger that you have validated yourself means you don’t have to trust a third party to be honest about the state of the ledger.