Didn't see a pdf of your thesis, except on your web-site[1]. But the version there (at least as it renders on my machine), has numerous formatting issues. For one egregious example, look at the letter spacing in the title and legend of Figure 2.2 (page 27): "civilia ns", "Pe rs ona lity s core". I'm sure the content is great, but using it as an example of Typst prowess, seems ill-advised.
I took a look at the repo and it's probably the fault of the the SVG of the graphs, not of typist itself. Now, you could have used typst libraries to generate the graphs but back then (2 years ago I think?) it was probably a struggle.
I don't see any issues with the title of Figure 2.2, but the legend and the x-axis label have weird letter spacing indeed. It seems like images like this are standalone (https://github.com/rikhuijzer/phd-thesis/blob/main/images/pe...) and probably aren't generated by Typst. So perhaps the weird spacing is not Typst's fault.