Exporting plots containing special characters using MMA 13.2 on Ubuntu

Question

Is there any way to export plots as pdfs correctly on Ubuntu?

An example of the problem:

ListPlot[{{1, 1}, {2, 2}}, AxesLabel -> {"\[CapitalDelta]", "#"}, 
 PlotLabel -> 
  "characters don't export well: \[Gamma] \!\(\*SubscriptBox[\(\
\[CapitalOmega]\), \(mn\)]\)."]
Export["exampleExportBugPDF.pdf", %];

Produces:

Is there any work-around? If that is not possible, what is the closest way to export plots such that they looked good when zoomed in.

There are previous questions on this subject such as Problem with special characters when exporting to pdf but they were apparently fixed in 12.2. Now in 13.2 I have same symptoms.

Other suggestions such as below don't change anything:

SetOptions[EvaluationNotebook[], 
  PrivateFontOptions -> {"OperatorSubstitution" -> False}];
SetOptions[$FrontEndSession, 
  StyleDefinitions -> 
   Notebook[{Cell[StyleData[StyleDefinitions -> "Default.nb"]], 
     Cell[StyleData["TraditionalForm"], 
      PrivateFontOptions -> {"OperatorSubstitution" -> False}]}]];

Exporting as .eps has the same artifacts.

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"13.2.0 for Linux x86 (64-bit) (December 7, 2022)"