

Tailscale is just a bunch of extra fancy stuff on top of Wireguard. If you don’t need the fancy stuff, using raw Wireguard can be more lightweight, but might require more networking knowledge.
The biggest thing Tailscale brings you the table is NAT traversal. On top of that it uses direct Wireguard tunnels as necessary instead of creating a mesh like you usually would if you were using raw Wireguard. It also offers convenient bits of sugar like internal DNS, and it handles key exchanges for you so it’s just generally easier to configure. When you do raw Wireguard you’re doing all the config yourself, which could be a pro or a con depending on your needs—and you’ll be editing config files, unlike Tailscale which has a GUI for most things. It also supports some more detailed security options like ACLs and I think SSO, while Wireguard is reliant on your existing firewall for that.
Here’s what Tailscale has to say about it: https://tailscale.com/compare/wireguard
I’ve messed around with Tailscale myself, but ultimately settled on running Wireguard. The reason I do that though is because I trust my LAN, and I only run Wireguard at the edge. Tailscale really wants to be run on every node, which in turn is something that raw Wireguard theoretically can do but would be onerous to maintain. If I didn’t trust my LAN, I’d probably switch to Tailscale.
It seems like multiple things are being conflated here and I’m not sure what the reality is because I’ve never used Plex.
Some people claim this has something to do with Plex needing to pay for NAT traversal infrastructure. Okay, that seems sort of silly but at least there’s the excuse that their servers are involved in the streaming somehow.
But their wording is very broad, just calling it “remote streaming.” That led me to this article on the Plex support website, which walks people through setting up port forwarding in order to enable “remote streaming”! So that excuse doesn’t really seem to hold water. What exactly is being paid for here then? How do they define what “local streaming” is?