Well, the list.txt has more than 125K rules on it, a lot of text, so did you never see any content being rendered in Notepad??
because if it was empty, I wouldn’t see a 4 in the size (in your screenshot) and in my case it is 4,443KB here in my computer, which would explain why it says 4 but not why it is blank, unless it was too much text for Notepad to open it.
But if it was empty, that will be the reason why it is not blocking anything, adblockers need rules, each rule will tell the adblocker what to do, if the file was empty when you opened like your screenshot and nothing ever appeared, that will be the reason.
In any case, just delete that 1.0.372 folder and restart Brave so the lists get downloaded again. That might fix it, but when you restart brave and you see the folder being re-created again, open list.txt again and see if now it is not empty, because it is weird it is empty but still not 0KB for example.
Also go to brave://settings/shields and make sure Adblocker is set to Aggressive, just because the Default is Standard and that doesn’t do all the job the adblocker could.
If nothing works, download and test using this list.txt and see if replacing the txt that is empty will fix the issue, hoping next lists download properly.
About the default.json, well, that will be a last resort if nothing works, but you just take the "url": information like: https://raw.githubusercontent.com/uBlockOrigin/uAssets/master/filters/filters.txt and add them in the custom filters section in brave://settings/shields/filters, which will not have any issues in the future because the lists update directly from the servers of the list maintainers, the only issue is you pretty much have to take some time sometimes to update the lists (Expires property is only supported in Nightly), because they update every 7 days. But you will not have any issues anymore.
But I am sure just re-downloading the lists will fix it, so do that first.