Why Bitcoin Mining requires "Hash Guessing" problems, even though Consensus algorithm exists to tackle BFTP? This post on CoinText explains Purpose of Hashing in Bitcoin Mining:


  The purpose of all the extra work is to prevent the traitors from sending false messages but serves no other purpose.


The idea seems to make the false/rogue attempts of Byzantinian nodes more difficult.

Since I am researching on this, would like the community's view(s) on:


We have Consensus algorithm in place to deal with false/rogue messages, then why is there a need to make the process more difficult by adding hash guessing work?
If we skip hash guessing work, how will it impact the resiliency or reliability of Blockchain?
Since hash guessing tries to make further rogue attempts costly and there is no value-add from the computation, can we route some other difficult problems to Miners to keep the message attempt difficult and still utilize resources to compute something of value?
The "consensus algorithm" you are referring to is predicated on the "hash guessing" you are trying to eliminate.
If we skipped "hash guessing," the resiliency and reliability of the blockchain would be completely destroyed.
This question assumes at least 2 false premises and cannot be meaningfully answered.