How is search index a moat? It's hard to build, yes, but there is no moat here and anyone can build it as long as they have infra, talent and money.
Also for Apple while I am not sure, but looking at the Android phones there is hardly any feature of Apple which hasn't been covered by some Android phone, so I don't think IP is an issue. It's just that overall quality is much more consistent for Apple across generations that it has built a good brand.
I don’t think you understand how moat is used in this context. A moat isn’t impossible to cross, just harder to cross than a lawn. Also, I don’t think you can saw two features are the same unless the quality is the same. Two sms apps are not equal if one of them occasionally fails to send/receive messages.
I agree that postman has a moat. I think it’s important to say that every company has a moat in that they’re organized, located somewhere, and have customers. The size of the moat varies. We can treat a moat as a scalar value of dollars to cross.
Every company also has a valuation, either through public markets, private markets, or discounted cash flows.
A house cleaning company has a moat of trained cleaners, existing client generation process, goodwill of existing clients, etc. If the value of their discounted cash flows exceed the cost of crossing their moat, they are vulnerable.
The argument is that crossing postman’s moat would cost much less than their private valuation, and their future roadmap is unlikely to build a moat that is significantly harder to cross.
Also for Apple while I am not sure, but looking at the Android phones there is hardly any feature of Apple which hasn't been covered by some Android phone, so I don't think IP is an issue. It's just that overall quality is much more consistent for Apple across generations that it has built a good brand.