Air-gap + dice + checksum is legit, that's the part almost nobody actually does right. The broadcast step is the leak though: pushing the raw tx through a random push_tx website hands that site your IP tied directly to the address you just funded, before it even confirms. Sparrow can broadcast through your own node or over Tor - worth doing instead of a public form for anything you actually care about.
Air-gap + dice + checksum is legit, that's the part almost nobody actually does right. The broadcast step is the leak though: pushing the raw tx through a random push_tx website hands that site your IP tied directly to the address you just funded, before it even confirms. Sparrow can broadcast through your own node or over Tor - worth doing instead of a public form for anything you actually care about.