Bitcoin needs a lock-up security feature

I'm not talking about staking in order to gain interests.

I'm talking about a basic secury feature.

Right now a criminal could point you a gun and force you send all your btc to his address.

In a future where fiat will be just a memory and everyone will have their whole life savings in btc, it's just unacceptable that this kind of event could happen.

I was thinking it would be great to have a feature that let us lock some of our savings.

For example, let's imagine I have 1 btc. I could decide to lock 0,90 btc and to keep just 0,10 btc for general expenses. In this way, if I got robbed, I would lose just 0,10 btc.

We could set a timer for every lock-up. For example I could set 30 days, so every 30 days my 0,90bct would unlock and I could decide if I want to unlock them again, unlock just a part, or to keep them all "cash" without locking them again.