I would guess it has something to do with intangible assets linked to fad usage. There are ten thousand people that could made a usable clone of Instagram in a day but none of them would likely come close to competing.

Untrue if you're entering say the car repair, grocery stores, heavy machinery, food production, etc etc.

So many days business are branded and everything that isn't has had it's margins shrunk to zero. You can't drop in replacements for FAANG or Microsoft or a whole lot of consumer products because they aren't and can't be commodities as they have set themselves up as walled gardens.

Good for business, investors, and valued employees. Bad for consumers.

Lack of interoperability or replacibility is the monopoly of the 21st century and when we get past it we'll be in the beginnings of a post scarcity economy.