It only destroyed (or will destroy) those who believe Bitcoin should be anything other than the reserve currency of cryptocurrency.

Other cryptocurrencies can provide the medium-of-exchange function and BTC will continue to appreciate because it is the reserve currency of all that speculation (and hopefully bona fide medium-of-exchange) growth in altcoins.

Note that I had explained in detail that Bitcoin was designed such that it can’be modified to scale transaction volume (without an oligarchy but in that case the oligarchy would extract maximum fees any way). And Bitcoin can never support real-time transactions. In addition to the other criticisms made against SegWit by others, Lightning Networks must become dominated by Mt. Box nodes and thus it will become a fractional reserve system with loss of value analogous to centralized exchanges.