In practical reality, if Russia were to attack Finland or Sweden now, the answer from NATO would be pretty much the same as if they were already members.
Really? Why is this true of Finland but not Ukraine?
"In response to the deteriorating situation in the Donbas, Russia abandoned its hybrid approach, and began a conventional invasion of the region. The first sign of this invasion was 25 August 2014 capture of a group of Russian paratroopers on active service in Ukrainian territory by the Ukrainian security service (SBU)."
https://en.wikipedia.org/wiki/Russo-Ukrainian_War#:~:text=In....
The latter is important, NATO is not a hired gun. Finland does have a stable border.
Not to mention Crimea, whose annexation by Russia is accepted by nobody.
Besides, Finland has been a close NATO ally for a long time, shares NATO values, our military is already 100% NATO compatible, and we are strategically and geopolitically a pretty important piece of the puzzle.
Sweden would probably get stronger support for other reasons, like being perceived as an established democratic western country.