While I think this is a valid take for the term "platform" I do think that "Platform as a Service" implies that someone else is running the platform and I don't have to deal with the headache of managing it, I just use it.
Yes, from the developer's perspective, someone else is running the platform (the platform team). (At least, as long as the developers can avoid assuming ownership of the platform by managing terraform files or something, which in practice I've yet to see anyone avoid...)
And this is true even if you're not using a product that bills itself "as a service", get somehow we never called the next machines that programmers never touched running a LAMP stack "platform as a service". It's almost as if the "as a service" part meant as a service to your organization.
In a company, there may me multiple teams, each doing there own projects, PaaS can be within the same company and provide a common way to do stuff without each team having to start from scratch each time.