It may be nice to have a “perfect” power distribution curve, but in the end it is meaningless. Stryd’s complete answer is here: https://support.stryd.com/hc/en-us/articles/360001177014-Weight-and-Height-Setting
Although it takes more effort, if your weight is rapidly changing it makes more sense to update your weight regularly else the power distribution curve becomes more and more meaningless over time. After all, it is your power/weight ratio that predicts performance, and older workouts are “retired” by the Stryd algorithms automatically…