Second, have you ever seen 3D printed glass under a microscope? It's full of voids and the surface is awful (at least the last piece I saw). For high temp usage, this will not work. This is also a very specific kind of glass -- borosilicate mostly, with some pure quartz work as well, and it's going to have very different properties than even garden variety soda lime.

In short -- maybe 50 years. But, lacking the demand, I doubt we get there at all.

There is also a very strong bit of "I don't know what the requirements are." A chemist will go to the glass blower and ask for something... they can describe what they're trying to do, but they've got no idea about what they need to actually accomplish it ("I'm trying to create bubbles in a fluid" or "I'm going to be putting a catalyst in an oxygen / hydrogen mixture to examine it while the reaction is taking place"). It is the glass blower that takes those requirements and makes the actual product.

Claiming that in 5 years one will be able to 3d print pyrex glass and glass blowers will go the way of the buggy whip makers is akin to saying that you see a renaissance of visual programming tools and in 5 years programmers won't be needed because you'll be able to have the application automatically generated.

I don't see it.

1) People who don't print, think its a microwave oven, just push a button, right? People who do print see it more as a complicated craft with very slow somewhat expensive learning curve, much like a table saw or ... scientific glass blowing.

2) Very small scale mass production with 3-d printing, once you've expended considerable effort, time, and filament, to dial in the design and the machine and the technique, is almost "push a button" easy, but you can't reach that stage until maybe five prints are done and the whole point of a master glass blower is there is exactly one of this new object on the entire planet and you're in competition with dozens of labs worldwide, some of which will take a day to make a new reaction flask and win the publish or perish race, and some that will take a month to make the same new reaction flask and they'll be the ones who lose the publish or perish race.

3) The other confusion is people thinking its like buying a screwdriver from China instead of from a local machinist, or downloading an app from the app store why reinvent the wheel. But a master glass blower is of the category of work thats more like buying a rocket engine R+D component that has never been made in history much less mass produced, or is more like writing the first app in its category. In that way, having a large team that needs to coordinate between the chemist, the engineer, the CAD guy and the 3d printer operator is the usual management fallacy of nine women making a baby in a month, surely the scientific glass blower can do it alone, cheaper, more reliably, and much faster than the 3d printing team could ever hope to achieve.

4) Its not insightful that if you're doing world class competitive research requiring world class labor to remain competitive, then switching your subject matter expert labor fields isn't going to fix anything. The research that requires a tech with 20 years of experience is going to have just as hard of a time, if not harder, in finding a 3d printer tech with 20+ years of experience as it will finding a replacement for the master glass blower who retired with 40 years of experience.

5) If you know the playing field is leveled for blown glass equipment, then the only thing thats certain about switching to 3d printed glass is it'll take time and money your competitors aren't spending. The issue with #2 is there is no mass production, the specific issue with #5 is you don't get bonus points for doing things the hard way or being intentionally obscure. If in an industry that publishes in English, you publish all your papers in Klingon, thats very impressive but you'll never get tenure with that attitude, everyone will always be ahead in a terrain defined by publishing in English. Until the majority give up on glass blowing custom gear, you'll always be at the back of the research pack.