It’s a client requirement. The customer is always right.
A client of a restaurant doesn’t ask a chef to cook using client’s recipe. A client of data visualization professional (sometimes) have a recipe (“add a pie chart here and use these exact colors”).
You can obey. And make your client happy with getting what he/she asked for.
You can suggest a better solution and make your client happy with getting what will help the client to reach their business goal.
To be a real professional you need to know when, why and how to say “no” to the client requirements (or rather “I suggest a bit different approach because…”).
If the client is not happy then either you don’t believe in what you’re doing enough to make others believe or it’s just not your client.
There is a pizzeria (with pie charts), there is a Michelin restaurant with chef’s vision. There is a time and there is a customer for each of them. In each of them the customer is always right. But you’re the chef on the kitchen. You can serve pie charts or you can serve science and art of a great data visualization. It’s your choice how to make your clients happy. Just remember that what makes your clients really happy is when their reach their business goals, not when they say “it’s a beautiful pie chart”.