Neither closed or open software is safer than the other in my opinion. If someone wants to find a vulnerability they will find a vulnerability. The only advantage open source maybe has that it’s harder to hide vulnerabilities for years and it’s more obvious if they don’t fix it. But personally I wouldn’t use open source just for safety reasons.

For me it sounds like more like a PR move. It sounds like they just want people to adopt Oracle Linux because now it’s the good thing and when they’ll have the chance they’ll do the same thing. Not necessarily exactly what Red Hat (and IBM) did but something that won’t benefit the community but them. But maybe this is just my superstition or something and it won’t come to this. I hope it won’t come to this but I doubt it