I think we can all look to our old Econ 101 class for the answer. The answer is supply and demand
Demand. It would seem very likely that the demand will drop. If for no other reason than locations aren't going to run out and buy machines for their routes. although the effect would not be evenly spread.... routes may not buy Pro... but then again... HUO people may drop from a premium to a pro. Regardless, the demand should drop.
Supply. This becomes tricky. On one hand... factories are stopping so that could reduce the number of pins for sale. However, if there is a big push for people/businesses to sell, and not replace, then they could offset the loss of factory production.
Bottom line... if the market's supply of machines for sale goes up, or stays the same, prices will drop. If the supply drops (from fewer NIB being built and people holding onto machines) then you can't make a determination on pricing (When supply and demand move up or down together you can't determine the effect on price without knowing the rate of change of each... and price elasticity... so it becomes pretty complicated).
What you can assume is that it seems likely that both the demand AND supply of NIB machines will go down. So it will likely affect different models, and model types differently... I could see the Pro market tank while the premiums being stronger. However.... you really can't determine the total effect... you have to use make an educated guess.
Used machines... pretty tough to determine.... you would suspect that the demand will drop and there will be an increase in used machines entering the market. So that would cause prices to drop. However... what % of used machines enter the market in order to free up $ or space for a NIB? IF NIB sales drop then maybe people are more likely to just hold onto their machines.
Having said all of that... who knows.