Fact my 2012 Mac mini with 16gb had green memory pressure while processing the same number of raw files while my M1 Mac mini with 8gb was pegged solidly in the yellow. There's no M1 Magic going on in there allowing the 8gb to magically behave like a proper 16gb machine. You're right that the native version of Lightroom may or may not be more efficient fixing or worsening this issue. I really wanted to get along fine with the Mac mini 8gb version as I plan on replacing it as soon as the next gen ones come out to minimize my investment, but I regularly import and edit more or less the same number of RAW files so I will constantly be hitting that ceiling.Hard to say based on what you say, since you're not comparing to an 8GB Intel version, nor with native software in both cases.
I have since placed an order for 16gb Mac mini and will now need to wait well into January for it.
I'll admit my use case is not that common as most will be served well with 8gb of RAM only.