Quanta Magazine tries to make these topics accessible for people with low knowledge regarding them, thus mentioning the Riemann hypothesis, although adequate and needed for, say, a lecture on the topic, would not really help this goal.
But the primes are obviously not random, independently of the Riemann hypothesis - they're determinate consequences of the number system. Maybe I missed your point
In 1933, A. Kolmogorov used H. Lebesgue's measure theory to define random variables. With that definition, could have a random variable X whose values are only prime numbers and such that for each prime number p and for probability measure P,
P(X = p > 0),
that is, the probability that X = p is positive.
So, with X, the prime numbers are random.
References:
With TeX markup, polished details on measure theory are in
H.\ L.\ Royden, {\it Real Analysis: Second Edition,\/} Macmillan, New York, 1971.\ \
Walter Rudin, {\it Real and Complex Analysis,\/} ISBN 07-054232-5, McGraw-Hill, New York, 1966.\ \
and polished details on probability theory based on measure theory are in
Leo Breiman, {\it Probability,\/} ISBN 0-89871-296-3, SIAM, Philadelphia, 1992.\ \
Jacques Neveu, {\it Mathematical Foundations of the Calculus of Probability,\/} Holden-Day, San Francisco, 1965.\ \
Uh, Joe, you have random variable X. What is its value?
Sam, just a minute. Let me draw a sample. Got one: X = 7.
But, Joe 7 is not very surprising or interesting. Is there anything else?
Sam, sure, one more minute. Got one!
Joe, well, then, WHAT is it????
Sam, sorry, it has 2^12345 digits and will take a while to print it out; this morning I have a coffee shop meeting with Susan; and I don't want to miss Susan, cute, pretty, sweet, smart, darling, adorable, precious ..., and single!
Exercise: Show that there is a random variable Y with the same distribution as X and such that X and Y are independent random variables. I.e., knowledge of X tells us nothing about Y.
The intuitive concept of random is closer to unpredictable given even everything else, that is, what probability theory defines as independent.
There are more details in Royden, Rudin, Breiman, and Neveu. To preview, there is a non-empty set Omega with a collection F of subsets that form a sigma algebra and a measure P on F. Then random variable X is a measurable function from Omega to the set of all prime numbers. So, for some point w in Omega and function X, X(w) is a prime number. Can think of w as a trial.
Uh, this morning I'm working on some Rexx code, so here I can't reproduce or compete with the references by Royden, Rudin, Breiman, and Neveu.
Stunning to me that a staff writer for a science magazine would type this sentence without referencing the riemann hypothesis.