If the GOP can get that 60% of the vote to 70%, they could flip MN, and Ds probably don't have enough room in the Twin Cities Metro to make it up.
If rural MN swung 10 point more Republican than how it actually voted this cycle, it would still not be sufficient enough to flip the state: Minnesota minus the seven county metro area is 45% of the state's population, so a 10 point swing in rural MN would translate into a 4.5 point statewide swing, and 7.1 - 4.5 = Biden would still have won by 2.6 points (still larger than the margin he actually got in either WI or PA).
For the GOP to break even with the Democrats, they would need to swing the rural vote by 7.1/.45 = 15.8 points. This is an illustration of the fact that the Republicans definitively can flip Minnesota, but that it's unlikely to become a red-leaning state like Iowa or Ohio anytime soon.
Of course, this is all assuming that the Twin Cities area does not swing further to the left (which could be a reasonable assumption with the right GOP candidate) or decrease in portion to the total statewide vote (which is completely nonsensical).
Oh yes, a 20 point swing would definitively exceed the 16 points needed to flip the state, but the margin of victory would be less than 2 points.
I think the other issue here is that MSP metro is growing over time. So, if MSP metro starts making up 50% of more of the statewide vote, then the equation essentially is can Rs get a non-MSP margin that's larger than the MSP metro. What makes this challenging is that you do still have the college towns, Duluth and Rochester mixed in with the rurals and they still lean D.
It is in fact one key difference between Ohio (and to some extent PA) and Minnesota, while in Ohio most small metros have shifted sharply to the right, in Minnesota most of them have stayed relatively democratic (Duluth) or have even trended left (Rochester).
