>This is wrong. Monopolistic behavior is anti-competitive behavior that doesn't require having a market monopoly

okay, sure. but it's only illegal when you have a monopoly.

In the U.S.

E.U. does not require a dominant market share to fine companies for monopolistic behavior.

It does, but: "In the AKZO v Commission case,[79] the undertaking is presumed to be dominant if it has a market share of 50%. There are also findings of dominance that are below a market share of 50%, for instance, United Brands v Commission,[74] it only possessed a market share of 40% to 45% and still to be found dominant with other factors. The lowest yet market share of a company considered "dominant" in the EU was 39.7%.If a company has a dominant position, then there is a special responsibility not to allow its conduct to impair competition on the common market however these will all falls away if it is not dominant." https://en.wikipedia.org/wiki/Monopoly

Which market would Apple be moving towards having a monopoly in, in the App Store policy case?

The mobile app market, there's only two companies in this market anyways, it's not that hard to prove monopolistic behaviours.

Who loses when Apple doesn't allow other payment systems on it's phones?

That's literally every company trying to increase their marketshare.

Anti-competitive behavior is different than typical growth operations.

I agree, that's my point. Growth moves you towards having a monopoly, but growth by itself is not anti-competitive.

It is not wrong. It's not monopolistic behavior without a monopoly. Anticompetitive behavior can lead to a monopoly and that type of behavior can be considered illegal. However, this behavior from Apple is not an illegal attempt to control more of the market. If anything it is net negative for Apple and their marketshare.

This boils down to semantics:

https://www.investopedia.com/terms/m/monopolist.asp

>In many jurisdictions, such as the United States, there are laws restricting monopolies. Being the sole or dominant player in a market is often not illegal in itself. However, certain categories of monopolistic behavior can be considered abusive in a free market, and such activities will often attract the monopoly label and legal sanctions to go with it.

While it is correlated, monopolistic behavior is not always from a monopoly. Suppliers in free markets can still exhibit monopolistic behavior without being a monopoly.