"the reintroduction of more of the Liquid Glass effect has upset people who heavily favor legibility over design."
Why would anyone want reduced legibility? Design is function, or so Apple seems to have forgotten. Design that reduces function? They are trying to kill Jony and make him roll over in his grave in unison with Steve.
Beyond the glass effect, which is a big yawn when it doesn't interfere with legibility, some of the other visual changes they've introduced are annoying and have no functional reason. Excessively rounded windows look odd on a Mac, but that's something one will become accustomed to with use, though I haven't yet. Making the left side bars on windows look like they are separate dialog windows floating above the main window creates both visual and function inconsistency in the UX. In particular, since the introduction of MacOS 10, the window control buttons have always been on the window they control. And they still are, except when you open the a left side bar. Then they appear to be on a separate dialog window. They still apply to the entire window, they just look like they shouldn't because of their position.
Apple needs to remember that design is function instead of adopting the standard industry idea that design is something added after the fact.