TL,DR: Unitree is making a real attempt to make their robots to be at least somewhat repairable, but these robots are still very difficult to work with due to glued connectors, tight cable managements, hundreds of screws, lack of availability of spare parts, lack of documentation, etc.
"Acme Corp is now selling the Alcubierre drive, but it is very difficult
to work with due to glued connectors, lack of spare parts and documentation"They just need a few more iterations.
Full self replication of a machine either from sand to silicon or through some yet to be developed process inspired by biology will be a fundamental change in how we do everything.
It will be akin to the assembly line and interchangeable parts in how it changes manufacturing.
Not any time soon. This requires the whole economy to build the core parts like microprocessors. It's sure possible even on lifeless rocky planets but will require a lot of resources from Earth to begin with.
There is also a biological way. Here we can start with lobotomized and chipped monkeys. But on other planets this requires the whole ecosystem.