the monster that kills screen printing will be from a machine that can decorate a tee shirt with dye evaporative or color modifying chemicals that will produce a soft hand image akin to discharge printing today.
I've had this same idea, if you could get like photographic paper and just expose the shirt like a photo, and then run it through the correct chemical bath to wash off the excess. Full color photographic quality prints with no minimum, expose the whole shirt and turn it into any color material. But has to work on 100% cotton because I'm anti polyester
Back on subject, Amazon is setting this up for one offs, not for high quantity production. Also they don't even need to match the quality of printing screen printing because if they have one picky customer, they just refund them for 1 piece, not one picky customer trying to get over on you for 100's or 1000's.
https://merch.amazon.com/Here is an example shirt -
https://www.amazon.com/Awesome-Narwhal-Shirt-Unicorns-T-shirt/dp/B017QGKO2E?th=1Walmart custom merch is different, they are actually going after our business model, but the benefit is that if someone is searching for custom screen printing, they are either going to find Custom Ink or Local options (i.e. us), and not really think as Walmart as a place to get custom goods, they get cheap toilet paper there.
So, Amazon and Walmart have their niche business, we have our traditional screen printing business, I don't think it is going to go anywhere, look at places like TeeSpring which have issues, they just have huge investments and then realize the ROI is not there to pay back investors, selling shirts is hard, screen printing is hard, and DTG while getting better still does not work well for spot colors, as well as specialty printing.
They are going after a different customer base, same as Printful or Represent, Printfection, and the other on demand fulfillment companies.
It's an interesting market, and I do think over time it will impact our business model as why would you carry huge stock when it can be produced on demand, but you take a hit on profit margin as the cost to produce one offs is higher, the results for traditional screen print graphics are not as good, and you can't do as much customization like woven labels, hang tags, so the final product is not as premium, which some of our customers are selling their products for $29-40 a shirt, which I don't think a DTG shirt will fetch without the extra bells and whistles.