I don’t agree about the movie being better, mostly because I think getting Mark’s inner monologue made much of the humor land so much better than the vocalized stuff in the movie. And they had to handwave a bunch of the more technical sciences and engineering that I found genuinely interesting in the book. But it was very cinematic and a pretty solid adaptation.

That's certainly fair, and probably more common among people who've gone into both with an open mind. There are certain things that books simply explore better than films, and the more in-depth "Swiss Family Robinson" competence-porn and meditation on isolation did work very well. Someone who wants that particular story with more depth and different pacing can always make a good argument that the book is better," but I do sometimes like to gently push back on the notion that any book is inherently better than its adaptation, not to make you a straw man or anything. :-) Also, for the record I really liked the book a lot.

I thought Damon did a very good job with converting the monologue into video messages and very much caught the spirit of the character. I honestly didn't miss the rover ride, which dragged and made an already constrained story positively claustrophobic, though the science and geography it showed was obviously core to what Weir wanted to do. I also just had a personal bugaboo where I struggled with the fact that every book character other than Watney was drawn thinner than thin and had clunky dialogue, so I found it a chore to wade through their scenes. The script doctors and professional actors made them much more palatable in the movie.

I think first-time-novelist Andy Weir just didn't really have more than one character in him at the time, and that character was his "juiced" author-insert. You can see him stretching his literary wings in Artemis but it falls flat in many ways, though that setting could result in a really good project of its own if they tweaked the characterizations some. PHM was nice because it kind of took a more incremental step of giving the author insert more flaws, making genuinely excellent use of his second character, and making the "plot device humans" comfortably deliver exposition and obstacles from the sidelines without being distracting.