NYT v Sullivan is only relevant to public officials - those holding or running for public office, which adds for them the requirement to prove 'actual malice.' In subsequent cases, the requirement has been expanded to employees of public officials as well as public figures - those who "achieve persistent fame and notoriety" and those who voluntarily engage in public controversy. In either case, the owners of a small company who have not voluntarily placed themselves in the public eye would be generally considered private individuals and thus the restriction on suing the media for defamation would not apply.

In lower courts there has developed some concept of an involuntary public figure. These are people who don't go out of their way to enter the public spotlight but who are involved in an event of overriding societal importance. So for example people being investigated by a government agency major crimes can't sue for defamation after being found not guilty. If JetBrains is actually under investigation then it's fair game, but if not it likely is still a private figure and this would be a pretty good example of a valid defamation case.

The problem is newspapers and journalists would be killed with a change in the law, and let TV "news" commentators like Tucker Carlson and Rachel Maddow to continue saying whatever they want.

The problem is that the line between news and commentary at this time is blurred. Hell; we can't even agree on what is true anymore just look no further than the election fraud claims made by the President of the United States.

Not really, it would just put the onus of deciding the truth onto the court systems, which doesn't sound great. JetBrains can't prove they weren't the underlying vulnerability so I have a hard time seeing any world where they would be able to successfully sue The New York Times here.