Follow-up If I had been clearer to my point, I would express that I mean with Bitcoin if you securely store your seed or private address, you can never look at it again and provided all goes well with the network, your funds will always be there, without having to trust anyone except the Bitcoin network itself.

Can this be done with Bitcoin on another 'layer' or any kind of known mechanism, real or theoretically?

Far as I can tell, all current solutions seem to involve a security trade-off / additional trust and continuous maintenance.