How is information in this blog related to Wikipedia article on DTrace [1] where one can read "DTrace is ... originally created by Sun Microsystems" and "Original author(s): Bryan Cantrill, Adam Leventhal, Mike Shapiro (Sun Microsystems)"?
Quite simply, it is not. The author is not claiming to have written DTrace, but rather, tools that made use of DTrace. From the introduction: "Sun Microsystems had just released DTrace" and "I was busy writing and publishing advanced performance tools using DTrace".
Sun developed DTrace the kernel building blocks, Brendan Gregg became an expert on it and made scripts that actually did useful stuff with them. The VIP was selling a GUI around Brendan Gregg’s scripts.
Brendan was the most amazing and prolific user of DTrace, from very early on. Brendan did not create DTrace, but in a sense he "made DTrace" what it is. And not just DTrace, but eBPF.
What do you mean? Brendan didn't create DTrace, he created DTraceToolkit and this VIP took his work and presented it as his own new DTrace-based product.
[1] https://en.wikipedia.org/wiki/DTrace