is there an article or document covering the value proposition and realistic timeline of Mars colonization available to read somewhere ? i certainly think it's good for humanity to do it but as a casual observer i imagine it will cost a lot of money over the next ~20 years as opposed to making any.

I don't know one off the top of my head, I learned most of my information about space and SpaceX from youtube, mainly from Scott Manley and Noise In Space.

This video gives an overview https://www.youtube.com/watch?v=G3hPH_bc0Ww but it strongly underrepresents the role of robotics.