A knife is not a knife. While any knife is better than nothing in a survival situation, there are knives better suited for certain conditions than others. As far as I read it, the question was a hypothetical, asking which one you would rather have with you-obviously, you will not have that choice in reality, but that does not make the question meaningless.
Any knife is a compromise between abilities. I know many people who call themselves bushcrafters will not use anything other than a four inch scandi, but that does not mean that it is the best knife for every situation.
The bushcraft blade (something like a 4” scandi grind blade/Mora), leans much more in design toward giving the user control and precision. The compromise it makes is that it gives up power. These characteristics make it a great knife for spoon carving, but far from the best option for a survival situation.
In a survival situation you priorities should be shelter and fire (especially in Northern Europe). Can you make a shelter with a 4’ blade?-Sure, if you had enough time and energy. With enough time you can make a log cabin with it, but it doesn’t mean that that would be my tool of choice for the job. Can you split logs for fire with it?-Sure, you can make wedges, and use all sorts of other tricks, if you had the time and energy. The reality however is that with a proper knife, i.e. a big knife you can do all those things much, much faster, and save a lot of energy. At the end of the day, that is what matters in a survival situation.
Of course, a knife that excels at shelter building/chopping, and splitting of wood, would sacrifice control and precision, and as such would not be as good for spoon carving. In a survival situation, carving is the last thing you should be doing.
If I had a choice, I would rather have a RTAK II, or at least a RAT 7 with me if I found myself in such a situation. Think of it this way: you are dropped into an area without any tools. On the ground you find a knife. Which knife would you rather find there-a Mora or a RTAK II?
By the way, because I’m sure someone will bring up the F1, the F1 is used by the air force as a survival knife because pilots have size limitations to the blades, i.e something you can carry on your body while in a plane seat. It is the same reason why US pilot survival knives are relatively small. The other branches of the armed forces use larger blades.