It depends on the stakes. Professional sports all over the world compete. They establish a standard framework, then expect the teams and referees to carry out that framework. Events happen in a wide variety of conditions, some even offer home court advantage.

So in a sense I agree but if your definition of "differently" is sufficiently narrow then every competition ever has played "differently". I think in a broader sense the question is can we make competitions on different machines in different locations 'same enough' to have a meaningful competition. I think the answer is yes but it may require changes to how we hold competitions today.

Nearly every organized competition. NBA, NHL, even non-sports like baseball and golf. They have a common framework used to compare events in different arenas, players, referees, weather conditions. Every organizing body sets a common framework in their rules, knowing there will be differences in many factors.

NBA events are held at more than thirty different locations throughout their season. Only about thirty of the five hundred or so players are in the same place at the same time.

You seem to have a rigid view of what constitutes a competition. As the capabilities of our equipment change, the nature of our competition may change too. Time will tell.

Selfie leagues are still sanctioned. They just only generate WPPRs for the finals portion, the selfie part is used for seeding.
https://www.ifpapinball.com/menu/ranking-info/

Matchplay generates & tracks ratings independently from the IFPA. Two totally separate systems. Matchplay uses the IFPA API to pull your IFPA number and associate it with your Matchplay name so when the TD submits results they are less likely to have to look up a bunch of player numbers. Matchplay's website runs in a browser so there is no need for an app.

I don't know what Andreas had in mind with the Matchplay ratings. The IFPA system has its weaknesses, maybe he's just generating data to see how he might improve them?

I use Pindigo to track what machines I've played. It has a lot of functionality besides that and I think it's a great app.