You've not established that your suggestions are core principles of modern economics or derived from them.
For example, you are asserting there would be 'no reason to own property beyond a certain age'... which isn't supported, and then jumping to the conclusion that that would lower savigns rates.
None of this is clearly true, just supposition.
> which isn't supported
The general consensus amongst most economists is that humans behave in a rational way? Not spending all the wealth you before you die would be irrational if your children won't inherit it.
Of course in reality that's often not the case especially these days so it might not be sufficient enough.
> clearly true, just supposition.
Well by such standards every discussion on any policy that hasn't been tried is meaningless because there isn't any empirical evidence.
> Not spending all the wealth you before you die would be irrational if your children won't inherit it.
Sure, but that's only one small aspect of the economy.
Maybe younger generations would earn more with all the spending and save more knowing there is no inheritance coming.
You only look at one aspect, claim you know what would happen, and the proclaim yourself right.