It may also spell trouble for horizontal scaling. A 128 core computer with a few terabytes of RAM could handle loads that that would otherwise need dozens of computers. There are huge advantages in terms of ease of management and programming.
If we're just running several processes there's not much difference from just running 8 computers each with 16 cores.
You need interprocess communication that works across machines.
You need to orchestrate the deployment of software.
Communication within a machine is much faster.