Tldr; security reasons...
So implement Segwit through a mechanism that introduces new attack vectors.
Nope. Still doesn't make sense.
Do you recall how irritated your fuck-buddy, Jihan, was that segwit would no longer allow him to engage in covert ASIC boost?
Nope.
Jihan isn't my fuck-buddy. Indeed, I've never met the dude.
I don't recall that Segwit no longer allows for ASICboost.
I don't recall any credible evidence that Jihan ever profited from covert ASICboost.
I don't remember any demonstrable irritation on Jihan's part regarding segwit's impact upon ASICboost.
But feel free to bring forth any evidence that might cover my knowledge gaps. (as if)
::ahem!::
More importantly, your deflection has exactly zero to do with the fact that the implementation of Segwit introduced novel attack vectors to Bitcoin. Perhaps we should discuss this first, before deviating to your smokescreen. Hmm?