But I get why Finnish would feel difficult for someone not used to hearing it from childhood. Unless you're Hungarian:)
I have no reason to doubt that.
I'm sure most anybody could pick up some conversational Finnish, just like any other language, but it depends on the morphology of the cases, and if there were many pronunciation difficulties.
Also if the cases are divided up into a number of classes of declensions to where you have to recall immediately which one any given word belongs to. Sort of like, the nominative plural of "apparatus" is "apparatus," not "apparati," because they don't belong to the same class of noun declensions.
Hungarian, huh. Well, IIRC that's one of the comparatively few languages that is stress-timed, like English, so that might be easier for a native English speaker who gets confused about the vast majority of languages that are syllable-timed, such that every syllable gets its own little time unit.
More or less.