On what OS are you using these settings? I found that Windows will refuse to allocate more virtual memory when the commit charge hit the max RAM size even if there is plenty of physical memory left to use.

I have 64 GiB of RAM and programs would start to crash at only 25 GiB of physical memory usage in some workloads because of high commit charge. I had to re-enable a 64 GiB SWAP file again just to be able to actually use my RAM.

My understanding is that Linux will not crash on the allocation and instead crash when too much virtual memory becomes active instead. Not sure how Mac handles it.