Minimalist UX - Pen, Paper, & a User
Summary
You do not need a lot of tools to be a UX Designer, in fact, I believe you only need a pen, some paper, and a target user to build a product in a pinch.
User Stories Are All You Need
In the book "Hooked" by Nyr Eyal, Jack Dorsey talked about how all his team needs is a story from the user to create a product. I believe it. Most work I do in projects is gathering stakeholder inputs and user stories. That's what I need to create something the business needs and the customers wants.
I recently had an interview with a Fortune 500 company in Atlanta that has the top design program I am aware of internal applications. For an hour, I was given access to a user and stakeholder and had to come up with a solution using only a marker and dry erase board. I spent 50 minutes asking questions and documenting responses, 10 minutes creating 5 wireframes. I killed it :)
IT was easy because all I had to do was listen, write their issues down, and create a set of shapes that could accomplish the issues that seemed to overlap or be crucial to one of the people. There was no need for anything else.
Simplicity Also Helps With Creativity
I could be wrong here, but I believe the more low fidelity the comp is, the more imagination there can be when playing around with it. Pen and paper, especially just with simple shapes with no shading, can quickly convey a multitude of ideas due to its vague appearance.