Much of how Data was portrayed/depicted in those early episodes probably has much to do with how the character's own backstory changed over time. In the beginning, according to an early version of the show's Bible, Data was referred to as "Data, rymes with that-a." He was, according to this document, built by unseen aliens and discovered by Starfleet on a planet. SO it was originally supposed to be technology beyond the Feseration's capabilities. Eventually, that changed, (even the pronunciation of his name) and the Dr. Soong background came to be.
Why or when they made this exact change, I don't know. But it must have been some time before Datalore, which was one of the earliest episodes.
That might've been an interesting backstory. One wonders if it might've led to Data trying to find his origin, as Odo initially was.
It would explain why no one in the Federation besides Soong (and Flint) successfully made what could be considered a sentient android.