Do you think substituting canned pumpkin for oil in brownies will maintain the fudgey texture?

Same amount of pumpkin as oil in recipe?

Not in my experience. It's not a bad product, but it hasn't ever been a "brownie" in my results. More a dense flat muffin.

Yes! And pumpkin brownies are the bomb this time of year. Just make sure it's packed pumpkin puree and not pumpkin pie filling, which can have other additives and seasonings that can affect the overall brownie flavor.