I think just may be one of the most poisonous words for technical discussion, regardless of where it comes from (developers, product, users, etc). Every time someone breaks it out, conversation is narrowed or shut down. The worst case is the pronouncement that the implementation is “just a case of doing X and Y”.
Without actually sitting down to develop the change – supported by the compiler, test cases, real datasets, and actually having to worry about all the details – a discussion is by necessity going to involve some amount of fuzzy thinking and misrepresentation of the problem. As teams we want to minimize that as much as possible.
Just asserts an assurance of confidence that is likely misplaced. Many times I see this resulting in the frame of conversation shift to either refuting the new bounds, or simply losing sight of other possibilities entirely.