It matters because it changes what you can do after something gets in. Traditional antivirus answers whether a file is known to be malicious; EDR answers what happened, in what order, and on which machines, which is the question that matters during an incident.
The common failure is buying the tool without anyone to operate it. EDR produces signals that require judgement to interpret, and signals nobody reviews are worse than no signals: the record exists showing the warning arrived, and that it was not acted on.