tl;dr: Having swap is a reasonably important part of a well functioning system. Without it, sane memory management becomes harder to achieve.

To be clear, I don’t blame the poster of this comment at all for the content of their post – this is accepted as “common knowledge” by a lot of Linux sysadmins and is probably one of the most likely things that you will hear from one if you ask them to talk about swap. It is unfortunately also, however, a misunderstanding of the purpose and use of swap, especially on modern systems.