Is it more circular than your argument "I think it's plausible, so it's plausible?"
The 2nd strawman argument that you've made against me.
My argument is that diplomatic tension is rising between the states that adjoin the South China Sea. One of those states (Phillipines) has switched allegiances from one major military superpower (US) to another (China) just recently. The president of The Phillipines has denounced international organisations strongly (threatening to burn the UN assembly building to the ground, for instance), and is being investigated by the International Criminal Court for crimes against humanity.
Separately, the US, China and Japan are all having a stand off between one another over disputed islands right in the middle of the exact same region.
And if that wasn't enough, one highly unpredictable, volatile nuclear armed state (North Korea) is exhibiting increasingly bellicose rhetoric towards ALL parties.
If that doesn't sound like a plausible tinderbox ready to catch fire, I don't know what sort of scenario you would actually consider potentially dangerous. It's a serious threat, and it's only 1 out of many possible serious threats. It's likely there are even threats to the internet's operation that no-one could have imagined, hence my focus on margins of safety and risk analysis.
Now, how is any of that either implausible or a circular argument
I haven't said that I'm against an alternative to an increase of block size and I think it's good that you mention them. If these alternatives exist and are capable of solving the problem, why aren't they more thoroughly discussed in the scalability debate? (Serious question.)
These two look interesting. What is the combined potential, in transaction capacity per MB, of these two measures? (Is the second one Bitcoin-NG? Why was it not explored?)
If you're actually interested in responsible scaling, maybe you could investigate them too? But I doubt that you are, you've spent far too long defending your entrenched and dogmatic position, when you don't really have any good arguments to support it.
Edit: Don't forget that the original intention of the proposals we're discussing here is to achieve approval for Segwit by miners of the "big blockers" fraction to get rid of the stalemate. I for myself, for now, would be perfectly happy with Segwit alone for now and then let the Core devs decide further scaling measures.
Which part of "explore the possibility" do you not understand?
The orphan rate has been improved vastly now we're at version 0.13 - 0.14. The amount of slack that frees up COULD be used to safely reduce the block interval, but that would have to be proven on a test network before any proposal could even be made.
And maybe you have something to remember; Segwit itself is a blocksize increase, of 4x. A 4x increase is NOT to be underestimated in impact, increasing resource use by a factor of 4 is very large for a peer 2 peer network.