We could start by just going back to the original spirit of copyright: it's there to prevent multiplication, not to be invoked as a legal technicality to restrict how someone can use and enjoy a creative work once they already acquired a legitimate copy.
The idea that copyright law should prevent things like format shifting or making personal back-up copies of a song or movie someone already paid for is absurd to me. It's just the legal version of scope creep.
The idea that copyright law should allow people who sell software to impose arbitrary restrictions on how it may be used or whether that copy can subsequently be passed on to someone else or any other unrelated conditions for that matter, all because of technicalities about making transient copies when software is installed on a device or executed from RAM, is just the worst kind of legal sophistry.
I think there are reasonable arguments about alternative business models, particularly permanent sales vs. some sort of temporary rental arrangement. There's a danger here that for pure knowledge works we may shift towards a system where everyone has to rent everything, but I think it's too early to say that the market can't sort this one out on its own and the success of services like Netflix and Spotify suggests that other models can be useful as well.
In a some very limited cases, I think there are also valid reasons to restrict what the general public are allowed to do with software, but these are mostly regulatory issues where we already have similar concerns with physical devices, such as preventing someone who doesn't know what they're doing from bringing down a communications network by transmitting noise and effectively DoS attacking everyone else. But IMHO these cases should invariably be addressed with their own suitable laws or regulations, issued by the relevant government authorities for the common good, not by the original developers subverting the principle of copyright for their own purposes.
Otherwise, for a physical product that only includes software incidentally anyway, I just don't see any ethical basis for restricting what the customer can do with it just because of the software element, and abusing copyright law for that purpose just shows how broken copyright law has become.