I don't see how segwit helps here (how it does "instantaneous" stuff?), more like other way around: by ensuring small block side it grants perma-queue and therefore confirmation delays
Segwit as it is currently implemented removes the fixed block size, and replaces it with a variable block size which is 2-4x larger than current blocks. So it is very much the opposite of what you describe.
Bitcoin cannot survive without a permanent transaction backlog once the block reward subsidy is gone. Either we move to having inflation or there is a backlog.