This is an odd take to me. I understand why folks might be annoyed at having to change their existing modding flow; change is tricky sometimes, and comes with challenges during the transition. But *new* does not mean bad, just new. Larian has been both very up front about their plans (so this shouldn't come as a surprise), and very fanbase-friendly in involving the community in developing their mod support. The doom comparison to Bethesda doesn't hold up when you look at how Larian has approached this development.
I am personally very optimistic about the new tools. I think it's awesome that the company put time and resources into officially supporting mods. Give it some time for folks to start converting existing mods over to the new format, and give it some time to see what is possible with the new tools.
Larian also has said they aren't removing support for any existing scripting mods; they intend for folks to be able to keep using many of the favorite mods already out there, and that they are not trying to prevent anyone from using third party modding in any way. They have said you can still keep using nexus for mods if you want, they will just focus on officially supporting their own tools and system. Which makes sense! They have done this before with their Divinity Engine.
Of course Larian as a company cannot support or allow copyrighted material, or material that is "discriminatory, racist, obscene, libellous, offensive, or likely to adversely affect the reputation or goodwill of Larian Studios". That's completely reasonable and normal. Nexus mods has the same rules about what mods can be posted, just less oversight because of the volume they maintain.
TL;DR: Give it some time. New patches always break stuff, but updates will come. It's really great to see a company officially support modding.