To its credit, this doesn't promise that we can (or will shortly be able to) actually read Linear A texts, and it actually explicates that we won't be able to do that. But that's pretty much the limit of credit due to this article.
Linear A's connection to Linear B has been hypothesized since... well, at least as far back as when I was taught it in school, which considering how long it takes textbooks to update themselves to state-of-the-art archaeology may as well be time immemorial.
What it looks like the actual "groundbreaking" research here is, based on the sleuthing done in the previous version of the article that leads to an academic review of the work in question (here: https://bmcr.brynmawr.edu/2021/2021.04.30/). The layman's version is that it's a detailed analysis of the structural elements of the script to propose how the (unknown) language was encoded into Linear A, combined with some analysis of how individual glyphs varied in time and space--and this results in the conclusion that Linear B is actually a version of a regional [script, not linguistic] dialect of Linear A that was used to write a different language.