I entered 3D printing 7 years ago professionally, but I've been surprised by how this has continually improved even in the last 5 years. Quality for entry level machines has improved dramatically and ease of use, etc. Which doesn't change your fundamental point that it'll remain niche. But there are some patents from Stratasys and others that will expire soon (it was a bunch of FDM patents expiring that led to the first wave of 3D printer hype starting ~10 years ago), and that should help expand the market significantly. But you're right we won't be manufacturing everything with 3D printing.
A lot of these things are over-hyped, but can still produce long-term value. Just not like trillions of dollars a year type of value.
Last-mile delivery to medical clinics at 80mph night and day, rain or shine, straight line ignoring traffic or geography is a pretty massive advantage for just-in-time logistics... it makes the concern about deep cold chain for Pfizer much less pressing.
There are heaps of other niche applications, from remote location manufacturing to automating customer configured products that couldn't be done with traditional approaches, to parts for small fabricators in a range of industries such as aviation and motorsports. Inconel printing is enabling some truly incredible parts for motorsport.
I do agree it will unlikely replace mass manufacturing of cheap products, but I think it's role in manufacturing has far from peaked. You are right about Etsy knicknacks, but I think even prototyping hasn't reached saturation yet.
Small launch market is a tough one, especially given SpaceX's cost advantage, but Relativity keeps racking up investment. It's been rumored that their 3D expertise make them future-proof in case plan A, launching rocket, doesn't pan out.
[0] - https://spectrum.ieee.org/aerospace/space-flight/the-worlds-...
I am disappointed to see ideas that have failed to deliver for a decade like drone delivery (https://www.cbsnews.com/news/amazon-unveils-futuristic-plan-...) and 3D printing (https://www.economist.com/briefing/2011/02/10/the-printed-wo...) have a very long buzzword shelf-life, presumably because they are enduringly futuristic. First principles should tell us that most manufactured goods will never be 3D printed. There are entire fields of engineering dedicated to manufacturing processes, because the final material properties and cost of an item are affected by things like cooling rate, grain orientation, surface finish, tensile strength, and tolerances. 3D printing is another tool in the toolbox, not a replacement for the toolbox. I personally find them useful for ideation, but useless for creating finished products. It is worth considering that the entire market for 3D printers consists of rapid prototyping and Etsy knicknacks, and that it has been saturated.