It matters because it moves the relationship from reactive to planned. A client with a technology roadmap spends deliberately and is far harder for a competitor to displace, because the next twelve months of work are already agreed.
The common confusion is the title being applied to whoever attends the client meeting. The role is defined by the work: someone who can hold a budget conversation with an owner, connect technology decisions to business outcomes, and say no to spending that will not pay back. Handing the label to a senior technician without that remit produces meetings, not strategy.