Tim Sweeney correctly observes this, then continues to talk about "millions of hobbyist programmers". I do not believe that ISO targets, or even has any remote interest, in this market.
ISO is comprised of nation-state members who will inevitably mandate ISO standards as part of legal compliance. Various stakeholders actually participate in standardization efforts and thus also both already know the standard and are able to push it through. All of these categories (government, industries in highly regulated sectors and large stakeholders) have large amounts of capital. The amount of money required to fund a purchase of an ISO standard barely even factors in on a balance sheet.
Hobbyist programmers arguably make a lot of open source software that builds the foundation for today's and tomorrow's platforms. However, when the big bulldozers from the previous paragraph roll in, hobbyist programmers give way to highly paid employees of these giants; be it by merging a patch or be it by being worked around with a greenfield project or fork.
On the other hand, ISO has an incentive in charging money for their standards because this adds perceived value: If something is freely available, it is easier to dismiss it as a non-serious effort when debating whether it is worth to bind personnel for participation in the standards committees; the standards come across as valueless, worthless.
Looking at this vector of interests of the various parties involved, I see little reason for this state of affairs to improve.