The "hate" is for apps that only pre-package the GPT with a pre-written prompt and don't do much else. And the reason is, I think, because simply making a prompt template is usually not a significant enough value-add except for the most untechnical users. Most users can solve their problems just chatting with the GPT directly.

To get to the first part of your question: no. Every SaaS I've worked on for instance has included months if not years of creating intellectual property (often from scratch) so that the user's are receiving significant value over what they could do themselves.

Jealousy aside, I think they are poor business models because there is little to no barrier to entry.