1) A fdroid equivalent pops up, which them becomes a collection of fantastic open source apps, and soon develops a strong user base.
2) Google launches play store for iPhone, which will on day 1 get millions of users.
3) Meta launches metaStore, which so the only way to get Facebook, threads, Instagram and WhatsApp. This becomes the fastest growing store in a matter of a week.
One may personally not like this world - but imo it's a better world than the one we have - personally for (1) to exist.