Do I really need to send nudes before a shoot?
Usually, no.
A photographer or producer obviously needs to know what the person being booked looks like. That does not automatically mean they need fresh nude or explicit pictures made specially for them.
For a first application, a few recent ordinary photos often tell me more than a polished portfolio. Current face, hair, full body, tattoos, piercings, general shape. Nothing complicated. Portfolios can be several years old, heavily retouched or built around styling that has very little to do with how somebody looks today.
If somebody asks for more, one question clears up a lot: what exactly do you need to see that my normal current photos do not show?
Sometimes there is a sensible answer. A tattoo matters to the concept. A body change means an old portfolio is no longer useful. A producer needs to know whether a particular framing will work. Fine. There may still be a non-explicit way to show that.
What would make me suspicious is the idea that sending sexual images somehow proves seriousness. Seriousness can be demonstrated by communicating clearly, showing up, understanding the project and signing the agreement. It does not require creating free sexual material before a job exists.
There is also a difference between linking to nude work you already chose to publish and making something new because a stranger asks for it privately. The first is showing a portfolio. The second can turn an application process into content production without anybody admitting that is what happened.
If the requests keep getting more explicit while the project itself stays vague, I would stop and ask what the actual casting process is supposed to achieve.
For my own projects, explicit application photos are not required. I want to know what somebody looks like now and whether there is a real fit. If an explicit production later requires an explicit screen test, that is a separate agreed stage with its own terms. It is not hidden inside the application.
There is another practical reason to keep the application stage simple: private explicit images create their own privacy problem. The more copies of intimate material you send around before a real agreement exists, the more people and devices now hold something you may never have intended to publish. That does not mean a legitimate producer can never ask for relevant visual information. It means the request should have a clear purpose and be proportionate to the decision being made.
If the job later moves into an explicit casting or screen test, that is a much cleaner moment to test explicit camera work because everybody knows what the project is, who is present, what is being recorded and what happens to the test material. Application photos and an on-camera casting are two different stages and should feel like two different stages.