Welcome to the world of UX! The very act of designing is about trade-offs which means that we can never design IA that will make everyone happy. I am looking forward to a future where AI can generate IA on-the-fly personalised to each and every user. From my experience, if the IA you designed is rigorously based on user research but the client pushes back then it is highly likely the client and the user have different ways of organising, classifying or labelling information. What is 'logical' to the user, seems 'illogical' to the client. If your client is committed to being user-centric, use your research to show them that their users find the IA intuitive. If they are not... it is what it is.

Sometimes, clients envision an IA that doesn’t quite align with what’s best for their users. This is where we can bridge the gap by demonstrating the "why" behind our choices showing tangible user insights. And yes, it’s a dance between staying flexible and standing firm on what’s best for the users. But the goal should be to give IA the room to grow from each round of feedback, always with the user in mind.

Understanding the expectation of the client is key thing here. Whether created by AI or Human, design is subjective and likings are based on individual's visualization. So the only way to solve is collaborate with client and give iterative updates by addressing each feedback given by client.

Engaging deeply with all stakeholders, internal and external, enriches the design process. Utilize feedback loops and adapt your approach based on insights gained from various perspectives. Share your successes and challenges with your team to foster collective growth. Each project serves as a learning opportunity—learn what techniques resonate with your clients and refine your methods accordingly.

IA is a tool. Like any tool, you need to first consider what you’re going to use it for. Actually, I would say that clients expect a specific outcome, not the IA design itself. They might not mind the IA design at all. So if this question is asked, you have a different problem at hand.