Made maple syrup last year for the first time ever, with a mix of 7/16 plastic spiles and a pack of 3/16 inch spiles I bought from Amazon. Yes 3/16 inch, not a mistake, not 5/16 inch. As last year was a very poor sugaring off year (even the local sugar bush had extremely low production) I do not know if my low collection amount was also due to the smaller sized spiles. I used the larger spiles in my biggest trees. I am tapping Manitoba maples (box elders) which don't generally get as big or live as long as other maples and I am only tapping trees that are in my yard so I do want to keep the damage to a minimum as all my trees are precious. Should I switch to larger (5/16) spiles or will the 3/16 spiles be okay? A small reduction in the amount I collect would be all right with me if it is better for the tree.
I don't know where your information on 2020 production is coming from, but the Maple News reports that production in the US (Vermont, New York, Maine) was a record, also in Quebec. The industry provides guidelines for how many spiles in a tree of a certain size, so you might want to get the recommendations for your area. A study by Wilmot, Perkins, Stowe and van den Berg concluded that the flow was pretty much the same from smaller spiles, the small spiles did less damage to the tree and were easier to work with.