There's a difference between 3d printing and Star Trek replicators that you can comfortably live in. At least, I can. Vat food is vat food, whether it is cultured or printed IMC.
You don't need replicators.
By TL12 you have unlimited cheap fusion power and gravitics.
Anything you can imagine industry here on Earth in the early twenty first century can produce a TL12 society can do faster and cheaper.
They can build agricultural factories to mass produce plants and food animals, these can be multistory controlled environment facilities that can cater for greater than the Earth's population today. They can be orbital stations or asteroid bases.
They can synthesise any polymer, any alloy, any protein, any crystal etc.
They have robotic factories to mass produce the widgets needed for other robot factories to assemble anything that can be built at TL12.
Once you sit down and think about it the Traveller setting of a TL15 society needs a radical re-imagining.
TL8 is fusion and early gravitics - super spy technothriller
TL9 is mature fusion, mature gravitics and the discovery of jump, your typical sci fi setting.
TL10 is different how? What sets a TL10 culture above a TL9?
TL11 a better jump performance, but once again what sets a TL11 society apart from a TL10?
TL12 could easily be post scarcity, what would a TL12 society imagine a TL15 culture to be like?