The wrong question is “are we a WordPress shop or a custom shop?” The useful question is which constraints dominate: who publishes content, how unique the workflow is, and what happens if the product needs a second product inside it.
WordPress is the right default when marketing and editorial teams need to ship pages without a release cycle, and when the domain is a site with modules (commerce, membership, directory) rather than a net-new operating system for the company.
Custom software is the right default when the workflow is the product: CRMs, portals, multi-tenant SaaS, or anything that would fight the WordPress data model every week. Hybrids are common — a WordPress marketing site in front of a Laravel or Node application — and often cheaper than forcing one tool to do both jobs.