I write algorithms that operate on predictable amounts of data. It's very easy to work out the maximum amount of things we need to have and then allocate it all in fixed size arrays. If you allocate all your memory at startup you can never OOM at runtime. Some containers need over 100GB but like the parent comment said we've already bought the RAM.

Caches are automatically released by the OS when demand for memory increases.

How often are ooms caused by lack of ram rather than programming?

I don't think MacOS OoMs as Linux

(and to be honest the way Linux does acts on OoMs are quite debatable)