The needs of mass production Industry and Hobbies are vastly different.
The modern hobbyist can use the industrial machine design from seventy years ago. Sixty years ago,in industry, the bar feed automatic was overtaking the capstan lathe.
About thirty years ago, we visited a foundry in Spain. The designer was using CAD. When the design was finished, he clicked on an icon, and somewhere in the foundry a machine started machining the die.
Industry has moved on.
Manual machine tools are still used in Industry, but in Toolrooms and Prototype shops, for one offs; which is what we hobbyists do most of the time.
Our modern machines are designed and manufactured using computerised techniques. If they weren't, we would not be able to afford manually machined and hand finished machines. Think of anything that you make in your workshop, and cost the time at, say, £50 an hour, (Which is what Industry needs to cover Material, Labour and Overheads ) Suddenly that little fixture, or Traction Engine wheel, begins to look pretty expensive!
We make things for fun, not for profit, as a living, so our needs are quite different.
A relatively cheap hobby machine can be fine tuned and improved in detail (We have all done ). The cost to us is time and some material. On a commercial basis, the cost would probably be prohibitive.
A badly made, assembled and adjusted new machine is just as much expensive rubbish as a worn forty or fifty year old "quality" machine. Neither will be fit for purpose without a lot of input of money, parts and time.
Choose carefully!
Howard