It would be great if the article said they solved one and made good progress on techniques for the second that will likely work on next generation hardware, but the article didn't say that. I don't see how it being a matter of scale makes this acceptable. It's like the U.S. national labs unveiling the world's first exaflop supercomputer, with a footnote indicating that in fact the computer is only 100 petaflops at the moment.
Can you add context?
Measuring the speed of a supercomputer is difficult because there are several factors that control performance that affect benchmarks very differently. The most common benchmark in use is LINPACK, which measures how long it takes the computer to solve an appropriately large matrix equation Ax = b and then computes how many floating-point operations such an equation notionally takes. This has been criticized for various reasons, but it's what TOP500 measures.
Summit scored 143 PFLOPS on this metric. However, the press release called it a exascale supercomputer because it can issue 1 quadrillion instructions per second, so 1 exaop. To most people in the industry, the goal of exascale meant 1 EFLOP on LINPACK, so it really does come across as saying "We built a 1 EFLOP computer (footnote: only 143 PFLOPS)."
There is a lot of evidence that quantum computers (the gate model) or, equivalently, quantum adiabatic computing is better than classical computing. All of it is based on a family of conjectures about the complexity classes P, BQP, and NP.
Scott Aaronson's blog is one of my go-to suggestions for rigorous introduction to the topic.
That's an important distinction because it's significantly more difficult to achieve a fundamental asymptotic improvement instead of an iterative speedup for the same factor. If a quantum computer completes a task with complexity O(2n) that a classical computer requires O(10n) to complete, you don't have quantum supremacy. If your quantum computer can accomplish a task in O(2n) that your classical computer needs O(2^n) to perform, you've got supremacy.
Given that nuance, I wouldn't say it may be a matter of time before we demonstrate quantum supremacy. There is still an undercurrent of skepticism in the research community.
Additionally, it’s worth keeping in mind that D-Wave machines aren’t true quantum computers in the sense that they can’t perform Grover’s or Shor’s algorithms.