From the article itself:

The researchers found that Sky was also reminiscent of other Hollywood stars, including Anne Hathaway and Keri Russell. The analysis of Sky often rated Hathaway and Russell as being even more similar to the AI than Johansson.

I’ve watched Her many years back, and I’ve been following a lot of Johansson’s work in the MCU franchise; I don’t hear her in Sky beyond both voices being similarly aged “female” (can’t really assume the gender of the AI model) voices.

If there are statistical analyses that says otherwise, and aligns with at least some anecdotal evidence, then it isn’t “very obvious”.

Also, people calling out dissimilarities from their anecdotal observations, along with statistical evidence against your personal view doesn’t equate to siding with the company, or against some popular celebrity; but rather, simply calling out their observations. This is just a discussion as to whether or not the voice is similar, try not to get too personally attached to either parties.