What you should really want, if you like reparability, is a market for reparable goods. In general, it will be more costly than mass-produced integrated goods, but foisting repair opportunities onto every consumer product will ultimately make people less satisfied with the products on the market, and it will make those products less accessible (and more expensive).
As for cars, I think there's a real market opportunity to make your cars exceptionally open to repair, but I don't think mandating it is a good idea. Especially as powertrain designs become more and more complex, the likelihood that you will be able to correctly reassemble them dwindles. The onus must remain on the customers and technicians to meet the technical demands of repair.
A line in the sand must be drawn between "difficult to repair" and "illegal to repair". The first is at the hands of the customer, the second, the legislature.
As for software, sure, the DMCA is unfair, it should have been struck down long ago. It is being abused constantly, and serves little or no practical purpose except to enable abuse.