Completely agree. There needs to be some concept of a marketplace that doesn't have monopoly power, and a list of "fair play" rules around those. The only difference between Apple's actions and 90's Microsoft is marketshare. It's a similarly anti-competitive in intent.
European Union has some regulation for financial markets that have had similar issues in the past. The regulators must approve a rule book for market place, in this case of trading venue, which including onboarding and listing rules. Those rules must not discriminate against anyone - one cannot do arbitrary decisions to block or hinder someone. Everybody must access the markets fairly.
We already seen the regulatory outreach coming to app stores when EU ruled that Google was hindering the distribution of Aptoide store for Android.
