There are two pillars to managing RAM with virtual memory: the obvious one is is writing one program's working set to disk, so that another program can use that memory. The other one - which isn't prevented by disabling swap - is flushing parts of a program which were loaded from disk, and reloading them from disk when next needed.

That second pillar is actually worse for interactivity than swapping the working set, which is why disabling swap entirely isn't considered optimal.

By far the best approach is just to have an absurd amount of RAM - which of course is a much less accessible option now than it was a year ago.