It is true that comfort can be a factor in how much work we get done, and it's also true that different people have different preferences. However, it's important to note that comfort is not the only factor. For instance, if you have a comfortable chair in an environment that's too noisy or too distracting, you may find it difficult to focus and get your work done. On the other hand, if you have a simple stool in an environment that is conducive to productivity, you may find that you are able to work more effectively because of the lack of distractions. Additionally, comfort can be a sign of motivation. If you have a comfortable chair and you're able to focus and get your work done, it may be because you are motivated to do so. In other words, comfort can be a sign of how motivated you are to get your work done, and that should be taken into account when you are looking at how much work you are getting done.
Comfort isn't always the culprit when it comes to getting work done; there are other factors at play.