"...you can rent seek on proprietary peer to peer systems as well..."
I still use a non-proprietary one that predates Tailscale and that is not OpenVPN. It is small and simple enough even I, a non-programmer, can make modifications.
It's possible one ends up using client-server in order to achieve peer-to-peer because not everyone has an internet-reachable, non-firewalled IP address. Using some hosting company's server to run a "supernode" may be required. No traffic needs to pass through it if it is used only as a "rendezvous server" so the cost can be minimal.
Companies that try to compete with "free" always draw high scrutiny from me. Stop using that free software and start paying us. We added 100 unnecessary "features".
Not doubting this "corporate strategy" can succeed, at least short-term. Look at Slack. But these subscriptions are not for me.
Client-server versus peer-to-peer is misdirection. The real issue is proprietary versus non-proprietary. IMHO.