I believe they favour sleep mode where the ram is powered on and the state is kept alive on ram. Only when the sleep time goes too long or battery starts running low, they dump into SSD.

It's not the swapfile that's the issue it's having the swapfile also be used for virtual memory.

If it was only used for suspend that would be fine because it would only be written to when you suspend the laptop, which in the grand scheme of things is pretty rare compared to writes caused by virtual memory swapping.

Mac OS does the same in this regard though, but in my experience neither Mac OS or Linux are particularly aggressive at using swap anyway.

Yup, macOS dynamically allocates swap files on disk when they're needed - that's why you may see 0 swap space in htop, which doesn't mean that it doesn't use swap.

That’s interesting. I wonder can Linux be persuaded to dynamically alter the swap space from 0 as part of the suspend script?

I think if you were to use a swapfile and set swappiness to zero it should behave like this.

Brilliant! I think this is the going to be the answer. Have the swapfile but use swappiness to tell the kernel not to use it day to day. Thank you :D