If a farmer here buys fuels for their tractor, that is taxed and filed under the commercial venture of the farm. If the same farmer buys fuel for a private car, it is private consumption and taxed differently. Setting aside tax fraud, there is a very clear line between private consumption and consumption as part of the commercial venture.
The EU equivalent would be EU constitution allowing restriction on internation commerce but then considering commerce entirely within France to be internation because hypothetically people in France might have otherwise bought from Germany.
Free trade was one of the founding principles of the EU and shared regulations for food production are fairly often referenced when people discuss the pro and cons of EU membership. In some cases I have seen regulations relaxed in my own country in order to comply with the EU regulation, and at other times been made more strict, all for the goal of more trade between countries.
In Wickard v Filburn, the court effectively decided the federal government could regulate commerce occurring entirely within one state, on the theory that intrastate transactions could reduce interstate demand. That's an incredibly expansive and arbitrary justification, and effectively removed all limitations from the commerce clause. Invalidating that ruling would be a massive reduction in the power of the federal government to limit people's rights within a state, and an expansion of the power of individual states to make more things legal. (Note that individual states can already in general make things illegal that the federal government permits, so the primary effect of invalidating Wickard v Filburn would be to make more activities legal, rather than illegal.)
There would be a lot of fallout, and potentially a need for more targeted follow-up cases to confirm the legality of specific federal regulation that previously just relied on Wickard v Filburn; the outcome would not be 100% positive. But on balance it seems like a net positive.
If we do ignore that aspect, the Federal vs state regulations is the interesting aspect Wickard v. Filburn.