Again - does not stand up to the scrutiny of logic.
A team recently started probing at the limits of what the Bitcoin network can actually achieve. In terms of controlled experiments directly scaling transaction count, on a worldwide subset of machines, and recording the results. About time someone did this, eh?
AAR, they found that with today's satoshi client, and commodity consumer hardware, the system starts bogging down at about 100 tx/s. In terms of blocksize, that would be ~33MB blocks. So we obviously have considerable headroom in the system for improvement by means of simple increase of maxblocksize. This would consume about 25% of a single core of a typical 4-core CPU, with 16 GB RAM, and an SSD, while consuming about 3 Mb/s of network BW.
But they did not stop there. Due to the fact that allocating more CPU cores to the problem did not improve performance above this (i.e., that it consumed a smaller percentage of additional cores, with no increase in throughput), they postulated that suboptimal multithreading performance might be the root of the issue. So they refactored the code to employ contemporary concurrency design techniques. After such refactoring, the performance of the system - on the same HW - was able to process 500 tx/s. This would correspond to >150 MB blocksize. I repeat - on the same, consumer-grade, hardware. Of course, this results in an increased network BW consumption of 15 Mb/s.
So we see that, despite the maturity of the satoshi client (i.e., a decade of development by Bitcoin's supposed best), there is significant low-hanging fruit in the deficiency of the software design of the satoshi client. Deficiencies having to do directly with scalability. Deficiencies that -- so far -- have not been addressed by the core developers.
Whether core has nobody that understands concurrency, or whether they just deem scalability to be a low priority, is a matter of conjecture. But the truth is that the core developers have not:
- measured and published such transaction capacity tests
- determined where the lowest bottleneck in system transaction capacity lies
- coded up a fix to remove the lowest bottleneck to system transaction capacity
- measured and published results with the fix for this lowest bottleneck to system transaction capacity
- All this in a time when system transaction capacity is the hottest issue - and has been for about two years.
On the other hand, another team has. Who was it? A collaboration of members of the teams working on Bitcoin Cash.