If you haven't seen this before it's worth a watch.
Andreas explains why Big Blocks are not going to work. (watch time: 5-6mins, Petabyte Blocks & Streaming Money)
https://youtu.be/AecPrwqjbGw?t=11m39sSegwit in its current form can't handle hundreds of millions of users either. That was never what it was about. We needed a step up, a year earlier than we got it, and we had a few options to do so. For the current leg, and I repeat myself yet again, why was segwit better than simply doubling the blocksize? Nobody seems willing to explain that bit, for whatever reason.
Because Segwit is an upgrade that enables many new technolgies, L2 & L3. Technologies that will enable millions of TX's per second.
We don't need an incremental step in the wrong direction, as perfectly illustrated by Andreas, big blocks can never fullfill the Bitcoin dream, because PetaByte blocks are effectively impossible.
I guess if you think doing the wrong thing as a temporary fix, and incurring the associated Technical debt is OK. There is little I can do to defend segwit, but in my mind and the minds of many other developers, it's not acceptable, so Big Blocks are not an option at all.