Meaning that while Solaris had many technical advantages over Linux, it's not exactly a vibrant and growing community. Do you really think that any greenfield endeavor is going to pick Solaris as its OS?
Disclaimer: I just left a gig where I spent 6 years in a Solaris shop, and while there wrote an on-demand zones management system.
So in other words, your comment really wasn't about Solaris, it was about ecosystem and community.
As for "vibrant" or "growing", I don't know how you would objectively measure those things or to what objective metric you would relatively compare them to.
Even if the Solaris community is not what you desire, the technology is still certainly significantly advancing almost every year.
Disclaimer: I just left a gig where I spent 6 years in a Solaris shop, and while there wrote an on-demand zones management system.