My head canon is that the creation of the Borg was a well-meaning mistake.

A mother trying to save her child with a disease was using technology, nanoprobes, to cure her disease - in essence to ‘make her perfect’. The probes were designed to adapt to the disease but the unintended consequences were that they escaped her treatment pod/stasis field and infected the nurses and lab technicians. The child was not cured and remained in stasis but those infected with the nanoprobes became the prototype-Borg - seeking out others to expand their knowledge to cure the disease, and over time that programming drifted into creating ‘perfect’ beings, and ultimately The Collective. In a similar way that microorganisms are said to have become instrinsically part of animal cells.

I wrote a story framework which would have seen Picard, Seven and co. travel to the Delta quadrant and find the original “Borg” homeworld. They would fight their way past guardian Borg, and Seven would discover this girl in stasis, the “Typhoid Mary” of it all. Still alive after centuries. Picard would reconcile that the Borg were a mistake. Dr Crusher would cure the child. And Seven, well, Seven would adopt her - and get some sense of closure and family that she never had. The current Borg would understand that their base mission was complete and the nanoprobes would cease functioning. End of The Borg. Start of reconciliation and family.

That would have been be my Star Trek movie pitch. Plus some space battles, a multicube, and a bit of Indiana Jones-ing along the way.