I don't think it's that hard to rely on hardware development, it's more of a problem of rolling out a fleet of new hardware.
It's just not realistic to take all the switches, routers, and other garbage you've got in between points in the network off the rack/ceiling/wall/pole because the hardware can't support some protocol.
Good evidence for this is the rollout of fiber, which has been happening neighborhood by neighborhood and house by house for a decade.
I was mainly talking about your own dc but yes if you need to traverse public infra it’s a complete non-starter. But also it’s not like middle boxes offer you any sort of sdn api - you still need to overlay
It's just not realistic to take all the switches, routers, and other garbage you've got in between points in the network off the rack/ceiling/wall/pole because the hardware can't support some protocol.
Good evidence for this is the rollout of fiber, which has been happening neighborhood by neighborhood and house by house for a decade.