Reticulum gets around a lot of these problems, as the (better) encryption is app-level (or even more fine-grained.) Its also not tied to lora, so you can interop easily with other transports. I made a websocket transport for it, and there is already TCP and UDP, and a couple non-lora radio transports. I also made a (works on web) js and Arduino client lib, and it has a few native client libs, so it can sort of be used on anything, even over traditional networks, or web clients. Meshcore and meshtastic are way more popular, but reticulum seems so much better, to me, for most things. It can still have overload problems, like any radio network, but no client is required to forward, so you can build a different kind of network ("only forward messages that are for my peeps" and marked correctly.) It also has "it costs compute PoW to send to me" which can greatly cut down on spam.
I only recently discovered Reticulum, only to then learn that the developer has retired from working on it. Do you know if there's still any community members carrying the torch?