The DevOps model has morphed from "nice to have" to "must have" for any company that needs to move quickly from idea to production to product in users' hands. In fact, DevOps is table stakes. Companies are now looking to grow and more effectively manage DevOps with platform engineering and SRE (site reliability engineering) staff.
No one has these roles perfectly carved out right now - there's just too much to do and not enough people to do it - but knowing where these three disciplines do and don't overlap will help organizations evolve and take advantage when they are ready.
You might say that platform engineering is the next big thing in the DevOps world. Platform engineering is not brand new; it's an emerging model focused on not only simplifying developers' lives, but also empowering them with a set of carefully curated gold-standard tools.