SoftRAM wasn't as badly thought out as you thought. The idea was to use compression as a warm layer between "in-memory" and "on disk". That idea is actually implemented in windows 10/11 as "memory compression", and is in linux (zswap) and mac os as well. The only problem was that SoftRAM was half-baked, and their compression algorithm was memcpy (ie. nothing). Raymond Chen has a much longer write-up:

https://devblogs.microsoft.com/oldnewthing/20211111-00/?p=10...