Do we actually do this that often, though? Email and photo sharing are generally dependent upon third parties, and generally extremely centralized and powerful ones, such as Google or Facebook or Twitter. Very little Internet communication goes directly from one person to another.
If centralized entities can control your spending, they can control you. That's one of the core arguments for decentralized finance.
As for transaction reversibility, I am sure that a payment insurance program will crop up in the not-too-distant future to alleve those fears.
See, I see Crypto people mostly arguing that Crypto is going to take over a some huge percentage of transactions in order to justify some skyhigh valuation, and then when pushed back on whether it is actually superior for large percentages of transactions, they revert back to an argument that there are certain (normally politically motivated) transactions that its important for.
Unfortunately I don't see a universe where you can justify any of the valuations or importance of Crypto if the main use is the much smaller set of transactions.
Which loops back to the problem: why is anyone else going to buy in?
It's still being built out, it's not snapchat or some other anti-pattern app maze delivered by hungry VCs by a crack team of fresh grads with no moral development.
This is a protocol for financial independence. And yeah, it's new money. Old money that spends like money is the problem.
Maybe encrypted messaging like Signal is a better analogy. Yeah, it still passes through a third party, but they can't read it.
Even so, it seems like the apps that are the most centralized often have the most communication volume, and things like Signal and AirDrop, as nice as they may be, are largely outliers. This is especially the case when we look at group communication, where many participants are involved (Reddit, Twitter, Slack, Discord, etc). I find it very hard to have private group conversations on the Internet due to these platforms, as almost every community is stuck on a completely centralized+proprietary solution by now.
I think even still, the fact that you could go p2p acts as a behavior regulator for these companies. Gmail wants to charge you a monthly fee? Jump ship to a free competitor or run your own mail server.
It's the same way with crypto. If an exchange starts charging me for custody or ridiculous fees to transfer money I'll just download my own wallet and transfer the money myself.