What could be the career fallout for someone who is unwilling or unable to train to become a better communicator? Can workers today be successful if their writing is and remains poor?

No, workers today cannot be successful when their writings are poor.

Explanation:

Proper communication skills and good writing skills is very important for somebody to achieve success in their life and it should be learned by people.

A person who does not want to undergo any training for good communication skills will be at big disadvantage because :

--- it will affect the career growth adversely.

--- the person will  not be considered competitive and will not be preferred by the management.

--- there will be communication gap and he will not be able to communicate and express himself to others.

--- they will face a great deal of obstruction and improper communication can lead to big mistakes.

Workers or professional cannot be successful in their career if their writing skills are poor because :

--- they will not be able to prepare any reports or write any emails to their colleagues and to their seniors.

--- Instruction given to others in the organisation can be misleading and ambiguous if the workers are not able to properly communicate the written instructions.