It used to be that we inferred the efficacy of training by measuring learning outcomes. We still do. Most often that means having SCORM content report into a learning management system (LMS), record what happened, and provide an audit trail. SCORM still does this; it’s not broken.
You don’t need to replace your SCORM content with xAPI content; nor will you replace your LMS with a learning record store (LRS). Instead, xAPI and SCORM is an evolution similar to the Homo Sapien vs.