2) Tailscale's control plane model for peer distribution avoids every concern affecting IPsec in regard to protocol negotiation security and compatibility.
TL;DR, diverging from WireGuard & supporting AES (via protocol negotiation with hardware acceleration), would be relatively painless.
So yes, tailscale is compatible with wireguard, it's just not exposed by any of the major coordination servers other than mullvad integration in tailscale.com, but the clients will happily consume information about wireguard peers that do not run tailscale at all.
Now screaming internally because every router I've had that's supported Wireguard I wish I could have just joined into a tailnet directly for subnet routing... and I can't find anything else that just plays nice either.
To get other tsnet clients to connect to non-tsnet client you need to provide the connection configuration through netmap from coordinator server
You lose the formally-verified cryptography guarantees underpinning WireGuard & its implementation, though. That's a bigger tradeoff: https://www.wireguard.com/protocol/
You used AI to write that, didn't you? Please don't do that, it's disrespectful.
Anywho, given your strong conviction about this, consider suggesting to Jason on the WireGuard mailing list to swap ChaPoly for AES-GCM, or perhaps consider a fork yourself. Good luck.