Really, most of all, that's probably why they're not going to do anything with it. Unless you're old enough to have fond memories of the 80's iteration, or are one of the very small group who dove into them later in life, there's just no interest
As someone who came in at the 90s too, I have interest... after Renegade Rhetoric, because as you say there's no GoBot anything in our time and Jim Sorenson's work is the only GoBot fiction I've ever seen. (Plus it came out when I was actually around!) That's given me a genuine interest but I'm abnormal here. Only new fiction that more people can see would change that and there isn't any on the horizon.
See, it was the opposite for me. The issue with Renegade Rhetoric was that it was written with the assumption that the reader already knew the characters and lore of the GoBots. I didn't know more than the broadest of strokes, so after reading the first few, didn't bother, since I was a bit lost, and wasn't willing to sink time into doing research on it.
I mean, they seemed well-written, and a lot of care clearly went into them, they just read like they weren't for me. And since I'm on the high edge of that coveted 18-30 demographic, making anyone my age care is an uphill battle.