I hope you are right, and I'm wrong. I suspect this is a temporary, happy circumstance that we enjoy today, due to the segment of history we inhabit, but am concerned it will be reversed due to physics, further market segmentation, and an ongoing miniaturization mania.
As semiconductor fabrication processes get smaller, die sizes larger, and operating frequencies higher, I think we will see the hardware become more opaque. Already the test equipment to hack on cutting edge workstation- and server-class processors is spendy; just a 2GHz 10GS/s oscilloscope is 5 figures USD $ even used and just-calibrated. As manufacturers head towards greater integration on the die to differentiate themselves in a furiously- and constantly-commoditizing industry, we'll likely see more binary blobs at first, then market segmentation hits those of us who want open/powerful gear with a double-whammy. We enjoy the fruits of commodified hardware components now, but I'm not sanguine that state of affairs will last indefinitely due to the aforementioned integration trends.
As everyone noticed that personalized gear enjoys outsized margins, we're seeing ever-increased pressure to further integrate and miniaturize into smaller packaging; repairability and accessibility to the hardware not invited at all to the design party. I really wish this specific trend would reverse.
I suspect that the PC as we know it will morph into a greater walled-garden device in the next several decades, and if we want open/powerful gear we will find ourselves in a tiny market segment. At best, paying very high prices for the small volumes catered to, and at worst, in a technology ghetto.
For now, I agree with you, but the long-term constraints are not promising to me further openness of the hardware.