The thing to remember about IP, copyright, patent law, and the like is that, particularly in the domain of intangible "knowledge" and infinitely-duplicable "creative" works (such as anything that can be replicated digitally or whose material composition is irrelevant to its utility and content, such as books or movies)...they're designed to allow us to treat them as "property" in the same way we would physical property.
They're designed to protect "ownership."
The old-time gold prospectors of California and Alaska panned for gold for hours upon hours and days upon days for years on end. If, once they were done acquiring it, somebody else could just take a look at it and produce copies that were just as useful as the originals for a tenth the effort, these men would never have gone prospecting.
IP - intellectual property - is just that: it's property owned by somebody by virtue of the intellectual and creative work that they had to do to create it.
It takes effort to write a novel. Far more than it does to read and duplicate it. And nobody has a right to demand that, say, George R.R. Martin ever release another novel in his Song of Ice and Fire series. If, for some reason, he finished it this year, but decided that he never wanted the public to see it, there is no moral nor ethical way to say, "the conclusion of that story belongs to the public! He must release it!"
If Jed Clampett owns some back-woods land and discovers oil on it, and decides that he doesn't want to allow Exxon to come in and mine it out, no ethical nor moral way exists to demand that he give access to that oil. No matter how much we decide we need the oil, it's his until we offer him something that convinces him to sell us access. If Jed Clampett invested his own time and money into building his own oil wells, and then sat on the oil rather than selling it, we still wouldn't have any ethical nor moral right to demand that he give it away if he holds it for "too long" without "making it available." For whatever reason, the investment he put into it is not something he feels he's getting back. That means it's up to us to figure out how to convince him - how to pay him enough - to sell it, if we want it badly enough.
To try to force "sale" by deciding that not selling it means it's now something that can be taken for free, we effectively deny ownership to anybody. Without ownership, we cannot expect people to work to produce. (And yes, employees who don't own their work product still are paid what the employees feel is fair. If they don't feel it fair, they can choose to find other employment, or not work at all. If others will work for less than they feel they're worth, then they have objective evidence that it may be they who overvalue their production.) If Jed Clampett feels his oil is worth $10 billion per ounce, nobody will buy it from him for that amount. But he feels it's worth it, and thus would rather hold onto it than sell for less.
That's the other thing, addressing this proposed change to IP directly: it says it must be "officially available" or they give up their rights to the IP. It doesn't say how cheap that availability must be. Let's assume for a moment that the claim about GM sitting on a patent for an engine that would go for 60 miles to the gallon is true. To continue in this behavior of "refusing to sell," all they'd have to do is offer to sell engines - to be built on-demand - for $100 trillion. And raise the price as inflation goes up.
It's "officially available," but at a price nobody would ever pay.
And we can't say, "oh, well, that's not a fair price, so we'll establish a legal ceiling to how much something can sell for." At that point, you're just legalizing theft, again. Especially since "fair" may mean "free" to a lot of people who think that, say, a novel can be distributed electronically so cheaply that they shouldn't have to pay for their copy at all. Remember: a thing is worth what people will pay for it and what people will take to part with it. I mean, I would certainly pay $10 for a brand-new, fully functional Surface Pro 2, but I doubt I could find somebody to sell it to me for that. That means it's worth more than $10. But only I and the person from whom I'm buying can determine the value of the exact Surface Pro 2 I'm seeking to buy. Only Jed Clampett and his customers can determine the exact value of his oil. "The market" is really just an aggregate of all the individual purchases of the product in question. That's why "market values" fluctuate as things change in perceived value. When shortages occur, people who want it more desperately offer premium prices to get first dibs. This drives up prices overall as others strive to match or exceed them to get what they need. Attempting to say "it's only worth $X" from some sort of legal standpoint leads to true shortages. We had lines at gas stations in the late 70s precisely because of price controls.
Scarcity will be rationed. Whether by dollars or by "ration stamps" or by "first-come, first-serve," it will be rationed. At least with dollars, you know that somebody valued something the person offering them did enough to part with said dollars. (It's also why you wind up with a black market ANYWHERE you have anything short of a genuine open free market: it's the natural state of human industry. People will offer what they must to get what they feel they need, or even what they want badly enough. This drive will cause other people to offer those goods and services, eventually, because they want the price offered for them. Black markets are "expensive" only because the required threshold to get people to break the law tends to be higher than to trade openly. But they can be "cheap" too, if the reason for the black market is the premium of taxation/tariff/whatever put on a product by non-market forces.
You'll note that IP tends to fall into black markets - often FREE ones, such as torrenting files that you haven't paid for - because it's cheaper than paying the owner of the IP.
So our IP laws are definitely imperfect. If they modeled what they seek to properly, "black market" sales wouldn't be so prevalent. Then again, theft of property is always a thing with which one must be concerned...
...and I really am rambling, so I'll stop now.)