This is a common misconception. Because UX is under the "design" realm, it often gets lumped in with art. In my opinion, UX is closer to science than it is to art.
The main difference between UX and the classic "labcoat-style" science is that science strives to find THE correct answers to questions. While UX is very similar, the answers we are looking for are so varied and diverse, there is rarely a "right" answer. This is mainly because what is right and wrong stems from the opinions of our users. Different users trying to accomplish different goals in different situations. All of these variables lead us to a multitude of options that could all work, but some work better than others for a specific mix of these variables.
The sciencey-part comes from the iterative process that makes up the heart of UX. By continuously testing our hypothesis with different design methods, tools and strategies, we can inch closer and closer to a solution that works for our intended users.
While it is nice to be able to come up with ideas based on your own experiences, it is possible to come up with creative solutions without being creative yourself! One thing I love about UX is often, the best ideas come from your users.
For the designers who might not be brimming with creative ideas, there are tons of workshop strategies and research options to take advantage of. You would be amazed at how novel insights and solutions often float to the top when you get a bunch of your product users talking. By setting up effective use cases and requirements, potential solutions and ideas can be distilled from the collective creativity of many people who are not you.
In many cases, the expertise of your team (such as engineers, stakeholders, PMs,) can also be leveraged through structured brainstorming and ideation sessions (SCAMPER is a good example of a creative thinking framework). With so many resources at your fingertips, it is 100% possible to come up with creative solutions without being a creative person yourself.
That being said, if you fancy yourself a creative person... 100% power to ya! It is fantastic to be able to brainstorm on the fly and use your own ideas to promote discussion to inspire others. UX is creative in the sense that you might very likely end up with a very "creative" solution. What I mean by that is - the solution could be quite intuitive, but takes a few leaps of logic to come to fruition. Rest assured the ideas that led to these solutions RARELY came from a single "creative" person sitting at their desk... it is usually a team effort.
Because often UX projects are not seen as a "piece of art", any feedback that comes from testing will be at an arm's length from you as the designer. You simply work the feedback into the next iteration and test again.