Manually updating a config file to enable the web server was a wholly unnecessary step as that's just a toggle in the "Storage" section of settings.
reMarkable software has its faults, but I keep coming back to them for the best-in-class hardware, developer-friendly platform, which itself spawned an active developer community. Could it be an easier platform to develop on? Sure. But that hasn't stopped a huge number of supported mods being made available
There is indeed a "USB web interface" toggle under Storage. I've added a note in the final section, thanks.