How is it going to be easier? Now if they want to change the messages for success and errors, they have to modify several python files, one javascript files, various templates in HTML. Don't you realize how this is more difficult than just modifying the HTML? Also, what happens if for some reason there is a bug in the server and the message it sends you is one you don't expected? For example, in other systems it happens that when you query a database, an error can be "Table users does not exist", and just like that, you have told everyone you have a table called users. There are several problems with this approach.

I don't know why you decided that you only put error messages in the HTML when you cannot get them from the server. That's not what we talked about. Why didn't you consult me before doing it? Why didn't you add a comment in the diff? Or maybe even a comment to explain it? Without that, I could've missed this and this would go into production.