Paul Crowley:

One trivial example of signalling here is the way everyone still uses the Computer Modern font. This is a terrible font, and it's trivial to improve the readability of your paper by using, say, Times New Roman instead, but Computer Modern says that you're a serious academic in a formal field.

I don't think that these people are signaling. Computer Modern is the default font for LaTeX. Learning how to change a default setting in LaTeX is always non-trivial.

You might argue that people are signaling by using LaTeX instead of Word or whatever, but switching from LaTeX to some other writing system is also not a trivial matter.