Seeing as I just set this up, I should note down what I did.

Max upload size is too small

I need to upload lots of big images so fixing up the upload size limit was a first step, this is the advice I used: https://www.kasareviews.com/fix-upload-max-filesize-wordpress-error/
Specifically:

upload_max_filesize = 20M
post_max_size = 32M
memory_limit = 128M

The reasoning being that: the biggest file will be 20MiB, it'll be included as part of a POST body that could be larger because it has to encapsulate it on the wire (and in theory there could be multiple images in a single request), and PHP needs enough memory to receive and process the file.

Disable comments

Yeah look, I just don't want comments. I don't want to deal with them, see them, antispam them, etc. It's not worth my time. This is a place for me to dump content that doesn't suit twitter and is irrelevant to shortgirls.net, and needs richer presentation than my wiki affords, so I'm not interested in taking comments.

Screenshot showing how to disable commenting in the WordPress Settings interface
Disable commenting on new posts by default, easy!
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