The article says that the viewership is up from last year, I know.
Compared to Wimbledon and the U.S. Open, even the Australian, Roland Garros seems less accessible to the U.S. audience.
Roland Garros barely got any media coverage in mainstream media. Only NYC sports news the women's final got less than 30 seconds, the men's got a bit more because Nadal is a known name.
Even the fact that two U.S. players (Sloane and Madison) reached the SFs got no coverage in the mainstream media.
I hate to say this but since ESPN has basically abandoned the clay court season (and tennis in general, to a certain extent), there has been scant broader coverage of tennis outside of the very small, insular tennis media.
Not everyone has TC, which tends to favor U.S. men (who, per usual, did poorly at RG).
You can't grow a viewership this way.