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.
I don't understand why Prusa thinks keeping their designs proprietary addresses the "unfair competition" problem they seem to be concerned about. Anyone wanting to release a printer can use freely available designs, like those from Voron. The openness of the Prusa Core ONE is not what would allow a competitor to enter the market "unfairly" with a competitive product. Maybe it would make sense if they were bringing some new innovations to the market, but for a catch-up product like the Core ONE restricting access feels like slighting your customers for no gain.
I tried to stick to Prusa stuff through the release of Bambu products in order to support the notion of a group that can give-take within the OSH concept -- now they offer zero value comparably.
The Bambu products are better if you're willing to buy into proprietary stuff and you're not willing to put the leg-work into building something proper-open like a railcore.
Really sucks, but the writing has been on the walls for some time -- it has been harder and harder to find source/designs/models/etc regarding Prusa machines since the MK3 period.
Remember that Mr. Prusa himself has an open source logo tattooed on his arm. This must hurt him as much as it hurts us. I see myself as a huge proponent of open source ideals, but the company needs to make money, so I understand this move. It feels less bait-and-switch-y than the relicensing of other prominent foss products.
Doesn't the Core One share a lot of common parts and accessories with the Mk4? An upgrade kit is promised.
This is a terrible mistake. People see Prusa as a premium brand mainly because of its long history in open source. You can buy a similar Creality printer for like $200 from Amazon vs Prusa's $800 or whatever shipped from Europe already.
Barring any overwhelming breakthrough, other brands have them beat on price and performance. Hopefully they at least keep middle of the road models as open-source for those who really value that. I anticipate that the open-source printers will outsell the closed-source ones, unless they conceal the fact that they are now closed source.
By the way Prusa, if you don't want to help the competition, maybe don't let Prusa Slicer slice for other printers. But that cat is out of the bag, and it's also probably a marketing tool at this point.
Getting a bambu soon. Happy I didn't go for Prusa, as the open source aspect was the only advantage
There are too many cheap clones. Too much stealing of the open source work. This isn't remotely shocking, just look at Redis, Elastic and many many others... Open Source works until it doesn't.
I don't buy Prusa because they are OSH, I buy them because they are great printers. They are an open platform, if not open source. Which is good enough for my needs. If these changes they are making will allow Prusa to keep producing world class devices at reasonable prices, then more power to them.
And yes, I know some people hate Prusa or have had major issues. But they do a lot to move 3D printing forward, rising tide lifts all boats and all that jazz. We want all respectable and reputable 3D printer companies to succeed - because then everyone wins.