Accessibility is often treated as actions that have to be implemented like checkboxes. In this scenario, contrast, alt images, and tagging will create structure. However, in real-world scenarios that involve advanced frontend systems, accessible interfaces are products of architectural decisions.
In a practical scenario, as a senior engineer, there are multiple factors of influence apart from the coding aspects. The impact radiates to the workflows of development, component systems, and patterns, which are used or created by others. If there is no strategy incorporated during construction for accessibility, there will be difficulties or bridge gaps that need to be crossed when trying to patch this problem later on, causing multiple regressions.