the higher certain is +2h relative to that worth?

Underneath such a rule, miners may simply set each block timestamp to twenty minutes later than the earlier block timestamp – ignoring actual world time completely – and get a 2x issue discount each 2016 blocks.

On this means, all the community would have the identical worth.

Sure, however it might fail at its function: tying block timestamps (roughly) to real-world time. With none rule that relates block timestamps and nodes’ actual world clock at validation time, the 2 can’t be assumed to correspond.

And since real-world time is essentially exterior to the chain, any rule that gives this relation can’t be a consensus rule. It is a community rule, essential for Bitcoin’s safety, nevertheless it depends on data that isn’t a part of the chain itself.

Basically, the “max two hours sooner or later” rule is what makes the timestamps in blocks precise (tough) timestamps. It’s what brings actual world time in scope of the chain.