We don't hear much about Tableau Prep because most people are fascinated by Alteryx. In my opinion, Tableau is consistent with it's brand - its quick to learn and simple to use. Its not as advanced as Alteryx so people tend to default to Alteryx.
As a beginner who has had a taste of both tools now, Tableau is definitely easier to grasp than Alteryx. From what we have seen and used so far, the concept is the same, you build on to each step to create a flow.
