Computational chemist here. The phys.org article is a pretty bad rendering of the original paper. The "theoretical interpretation" described in the headline is nothing new. The actual scientific advance described in the paper is an experimental (not theoretical) technique for measuring transition states of molecules, involving making them very cold so the transition states last longer. This lets us verify some quantum mechanics predictions, but we already had a lot of verification. Calculating small-molecule reaction paths via quantum mechanics has been a standard part of theoretical chemistry for decades. We can do it at a very high level of accuracy using millions of CPU hours, or at a passable level of accuracy using thousands of CPU hours.

Big molecules are still a challenge because the scaling of the accurate methods is very bad (N^4 or worse, where N is the number of electrons!). These calculations are something that quantum computers could theoretically do much better than classical ones.