At the technical level BCH has showed that the network is stable in production with 20 MiB blocks, but the goal and ongoing work is to support gigabyte and eventually terabyte blocks so it would scale to worldwide usage while keeping transaction fees low. The counterargument by Bitcoin BTC is that large blocks centralize the network, as not everyone can afford to run a full node. That's a different debate that I would be happy to discuss, but I want to start by pointing out that keeping the block size low also centralizes the network, as many users will not be able to afford the increasing transaction fees (which rose to $50 at recent times). Does it make sense to restrict the network so anyone can run a $50 node but not be able to transact on it? I think decentralization is a means to an end (electronic P2P cash), not a goal in itself. In other words, blockchains should be decentralized enough that no single entity can take control of the network, but too much decentralization is inefficient, so an equilibrium must be found.
I believe that is the hardest problem that bitcoin didn‘t solve. The hashrate is governed by the price and a arbitrary halving schedule. There is no mechanism to regulate the hashrate to a certain setpoint where attacking the network is not feasible. This issue becomes even more severe when the block reward is dominated by fees in the future. In that scenario the hashrate is not so much determined by the price anymore but the available block space and the utility of on-chain transactions. It is really hard to judge bitcoins security model considering all these variables. But for now the solution seems to be to vastly overcommit hashrate
It's easy to increase the block size, but it's very unlikely it would ever be decreased again, so it makes sense to wait until there is no other option.
More on that here: https://twitter.com/DocumentingBTC/status/139399717145689293...
And you can even buy books explaining this way better than I (or twitter) can.
That doesn't make any sense. Any actor, like for example a government, might seize (control) a blockchain by having overwhelming mining majority (51% attack), but that has little to do with the size of the blockchain itself.
The only reason one might have to think that way is believing the false narrative that a BTC "full node" does anything to secure the network. Only mining nodes secure the network, having a copy of the full blockchain is not enough.
Edit: typo.
The fact Bitcoin could be more efficient and chooses not to isn't really an improvement over being unable to be more efficient IMHO - in fact arguably it's worse.