I think the Apple Safari fix only secures webbrowser related Meltdown-hacks so it is a partial fix.

So computers separate one application from reading information passing through the kernel. Meltdown tears down these security walls and allows for programs to read the kernel without permission. Worse is that these securities are part of the hardware. So no matter what OS you run you are at risk. However, it has not be shown that this information can be exploited on AMD or ARM systems. Source

Well besides Meltdown there is also Spectre which I think nobody has been able to resolve yet. Spectre `tricks' one of your application to send the hacker confidential information. Every system (even cloudsystems) seem to be vulnerable to this Source

In conclusion, almost everybody owning a computer might have a problem :(