Fredericksburg & New Braunfels have major German culture and German buildings from the 1800s, but they are larger cities now as they have expanded, but the downtown areas reflect what you guys want, but ya' know, connected to the world via roads.
Most of Texas small towns have co-ops, communities of 3000 give or take, and it's all walkable and drivable (usually one road going through them linking towns via backroads)
Usually they are pretty self sufficient because they are isolated, but you still need roads to connect the outer farms and other towns for supplies to reach downtown, and when you want to travel to bigger cities for larger hospitals, cinemas, family, clubs, etc. In West Texas you need it especially because good luck growing anything there.
This author is just ignoring existing culture and trying to apply direct European culture ignoring the fact that immigrants from those cultures have already merged and influenced small towns across Texas.
My advice, take a road trip through the backroads that connect Texas, you'll get a large dose of many cultures, nice people, great food, and massive highschool football games for entertainment on Friday nights.
You just described a typical suburban 'smart development', which is not dense at all by european standards, and really it is just like a typical strip mall area eveloved a bit, but still way behind.