To be fair, modders haven't introduced new classes with new VFX, SFX, dialogues and armors up to the maximum level the game will offer. Sure they may functionaly work but it isn't that easy to match Larian quality.
I take issue with this as they are in no way comparable. You have larian who has all the tools to actually add the content to the game, where as modders are basically just editing and glueing the output files to make something.
If the modders had the tools, then it would be a bit more of a fair argument, but currently as a modder I physically can't edit VFX, as a simple example.
Instead of just adding the information and having all the necessary files generated, we have to manually edit all the output files. So for a display name entry, for instance, if we want to do it correctly, it means I have to edit 3 different files at the minimum.