What are benefits of writing a survey paper?
In many fields, well-executed literature surveys are widely read and widely cited because they help a lot of researchers not have to retrace the steps of the survey authors. Readers can quickly benefit from getting a big picture of the domain and then be guided into specific articles to dive into according to their specific interests. This is a very valuable kind of research contribution.
So, the primary intrinsic benefit would be that you would be providing a valuable service to your research community. By &quot;intrinsic&quot;, I mean a benefit that is its own reward--in this case, the satisfaction of sharing helpful research.
For extrinsic benefits that would justify the time and effort (that is, indirect benefits that lead to other things that might be valuable to you), a well-executed survey article would be widely read and highly cited, so your number of citations would go up. For this reason, a highly reputed journal would like to publish such an article, since they want those high citations. High citations in reputable journals should generally be good for your career.
All that said, it would be good to talk to a more experienced researcher in your field to get their assessment of if your ideas would indeed be valuable and appreciated, since it is often difficult to assess that yourself, especially if you are a junior researcher.