Expanding design principles and practices to inclusive design from accessibility

Accessibility as a design goal worked well in the past when specific design strategies and practices were implemented to cater for people with special access needs to the content or materials on websites. These days, with the diverse range of devices, user behaviours and usage context for mobile devices, many designers are using the principles of inclusive design as a starting point for creating user experiences.

Is the current thinking to advocate for an expansion or extension of design guidelines around accessibility to look at a more inclusive range of users and usage behaviour (and is it more practical)? Or is it better to start from inclusive design principles and that way you naturally also cater for people with specific accessibility requirements?