For people in the 3D printing space, the most important points so far are not the fact printers are designed on open source hardware, but:

1. That they are easy to fix. This is still the case with Prusa, and that's a good thing, together with their great support.

2. That replacement parts are relatively cheap. This has been an issue with Prusa: open hardware helps very little if you need to pay an unreasonable amount of money to get a nozzle and heatbreaker or so. Bambulab parts are much cheaper, even if the printer is completely closed.

3. The OSS nature & hackability of software: that, yes, mattered a lot, and Bambulab, Prusa itself, and many other companies benefitted from reliable and powerful open source software to drive 3D printers (slicers, firmware). This had the effect of accelerating the field.

A bigger danger than closed hardware is patents. Also in the field of 3D printing the feeling is that the small incentive to innovate (Prusa was really stagnating before Bambulab) was also a result of providing the same value instantaneously to all the competitors.

I believe in open source as an accelerator of society. I also like open hardware. However both open source and open hardware can fail in certain setups, and in this case it is better to move away.