Just because we can't solve all current problems doesn't mean we shouldn't solve any current problems.

If you want to prevent replaying as well, add a counter.

> Just because we can't solve all current problems doesn't mean we shouldn't solve any current problems.

Obviously not, but solving problems is always a cost benefit and we went from all spoofing is impossible to some spoofing is possible. What is the benefit of doing this and what is the cost?

> If you want to prevent replaying as well, add a counter.

It's not clear that would be able to prevent spoofing if the attacker could overwhelm and degrade the real signal.