The size of the whole pie has grown, and, yes, so have P2P networks.

However, centralized networks of various kinds have grown too. From application-level networks (e.g. networks messengers from Signal to Discord; payment networks from Visa to AliPay) to transport- and network-layer networks (e.g. cloud-oriented client-server topologies; Tailscale), you see growth in the centralized world too. While I don’t have hard data, I’d casually assert that that growth is comparatively far larger than the P2P growth.

Also, if you’re referring to Moxie’s classic post about centralization vs. decentralization[0], I think you’re mischaracterizing it; it doesn’t claim that P2P is altogether inferior, wrong, or any such thing. I’d summarize his point as being that anchoring your application to a decentralized P2P protocol makes your application development less agile. In other words, there are engineering tradeoffs there, between centralization and decentralization. When he weighed the tradeoffs for making Signal, he came down on the side of a centralized architecture.

[0] https://signal.org/blog/the-ecosystem-is-moving/

> When he weighed the tradeoffs for making Signal, he came down on the side of a centralized architecture.

And as a result, Signal has a single point of failure and hacker/governments attacks.