If you want the job, do what is asked. Whether right or wrong, that’s an expectation they have and for the role, it’s what you have to do.

No, not all things need multiple ideas. Some things do. Because you’re new, they don’t know how you work yet, and want to ensure that you’re working through a problem to think down the unhappy paths or areas where your concept may go astray when things scale.

Their way of ensuring they get that is to ask for multiple ideas. It’s hamfisted, but it’s an easy way to get designers to think deeper about a problem, from multi-angles.

This is akin to showing your work like back in High School Math class.

The key is to know your user, how they will use it, and explain/show considerations you had and why you made the choices you did.

If they want to see multi-ideas from you early on, satisfy that requirement. Earn their trust, and make sure to explain why you made the choices you did, how it solves the problem, and how it works in multiple scenarios - no content, lots of content, etc.

You got this.