My Downloads folder is gone. I did not accidentally press the Delete key. I am attaching a screenshot at the bottom of this message just to show I am not joking.
I tried to manually create a new folder with that name in the Home folder, but it says that name is already in use, which suggests to me the folder is still there but is hidden.
I then tried to run sudo xdg-user-dirs-update because it will create a “a full suite of localized default user directories within the $HOME directory”, according to the relevant Arch Wiki page.
I don’t know this command did anything, but the Downloads folder is still not visible.
Move to your HOME folder inside your file-manager. The only thing that got deleted probably is only the navigation point in the left bar you showed us…
…navigate from your HOME folder to the Downloads folder and add it to “Favorites” again, that should solve the issue.
I did. I also edited the title a bit for more clarity for others, and added the marker SOLVED.
Thanks again, also to @dalto and @jonathon for responding. Thank you all.