Imagine you got your license and then tasked to make a crud service with some simple UI because that is what is needed for the client and they cannot use unlicensed developers.
That wouldn't happen. Professional licenses vary by trade, state, cost of project, size of project, impact of work, etc, etc. If it's trivial, you don't need anything. If it is critical, you need a bunch. If it's in between, it depends. The world isn't black and white.
It's a common misunderstanding that a professional license would be required to perform any kind of work which is not true of the professional engineering license.
Imagine some military institution or government body needs a piece of custom but trivial software. I doubt they will be able to hire contractor with unlicensed developers to do the job.
Sure they will - the body shop guys still do the build, the staff developer still does the design and the project manager herds the cats, but they'll add a licensed software engineer to review the design and the load bearing parts of the build.
You'd also see service providers start selling pre-PE stamped services - which is hardly different from the whole "go buy your SaaS from X who is (compliance regime) authorized" today. Just like today when you build a house, your general contractor goes and buys a pre-engineered truss and hires a bunch of laborers to put it up per spec.
