Why can this be a threat for LRT?

Hong Kong’s Tuen Mun South Extension approved
https://www.railwaygazette.com/projects-and-planning/hong-kongs-tuen-mun-south-extension-approved/56718.article

Around Tuen Mun South, there are LRT lines from Tuen Mun. So, extended West Rail Line will compete with conventional LRT lines. I wish increased demand would negate reduction of passengers on LRT.