OBS is an open-source project. Bad actors may end up taking it and using it for their own ends.
Reading that article, it's using the OBS capture and streaming framework inside their malware to capture a screen and stream it to a remote server. There's nothing OBS can do to avoid that, without going closed-source (in which case the bad actors will just use the current open-source version), making it so that OBS cannot capture a screen, or OBS cannot stream to an RTMP server.
It's a little like asking when someone will fix the problem with a shovel where it can be used to dig a grave.
The shovel just digs. OBS just captures and streams.
The title of the article is also misleading, or at least very badly worded (or intentionally badly worded as clickbait).
It's malware livestreaming an infected computer's desktop out. Not malware sniffing data from people who are livestreaming.
