On the scale of clickbait headlines this is pretty minor.

Riemann hypothesis is an important problem that has gathered a lot of attention over an extended period of time. Is it the biggest? Whose to say. It is at least up there in the list of major open problems. Its not like its an obscure problem by any means.

In my mind, the justification for referring to RH as the “biggest” open problem in mathematics is its importance in numerous fields of mathematics. It’s hard to take three steps in analytic number theory without running into Riemann. Zeta functions — and with them RH — have transcended number theory and are fundamental objects of study in other mathematical fields, most prominently representation theory and the Langlands Program.

That Wiki page even has a section about the RH:

> The Riemann hypothesis is noteworthy for its appearance on the list of Hilbert problems, Smale's list, the list of Millennium Prize Problems, and even the Weil conjectures, in its geometric guise. Although it has been attacked by major mathematicians of our day, many experts believe that it will still be part of unsolved problems lists for many centuries. Hilbert himself declared: "If I were to awaken after having slept for a thousand years, my first question would be: Has the Riemann hypothesis been proved?"

Your complaint here is that vernacular English ("biggest") isn't as precise as mathematics?

Eduard Frenkel does a pretty good job at it: https://m.youtube.com/watch?v=d6c6uIyieoo

Isn't this a Physics problem?

Here, but as the other person commented: TFA's link is not paywalled for me neither...

https://archive.is/9AT4O

FWIW, it's not paywalled for me (even in incognito mode).

First major improvement to the bound since 1940. Many other things can now be improved as a result, that depended on the earlier bound.