Kaunertal was great, perfect weather, great snow and few people

But they aren't going to send your data to the Finanzamt, they just want to make some $ doing arbitrage

You can just use lightning (Robosats) or do a coinjoin/swap.
The benefit of no-kyc is that your trades aren't being documented and reported.

GM

Applied Science
Hyperspace Pirate
Asianometry

Maybe this implementation is useful
https://github.com/Legrandin/pycryptodome/blob/master/src/chacha20.c

TEEs like Intel SGX/TDX allow this today (trusting just the CPU, but that is trusted already).

Onchain/Taproot

It's possible, but a bit hidden.
In the top left menu go on Adresses/Coins, then long press a utxo to select it and a "Freeze" button will appear at the bottom.

Electrum has a TUI. Just start it with -g text.

Also doesn't need a static channel backup as you can force close channels just from a seed backup.

https://electrum.readthedocs.io/en/latest/cmdline.html

You can also try Electrum (as daemon), there are maintained plugins for NWC and lnurl and you don't need to run core alongside as it can use public Electrum servers (however its good for privacy to run your own).