As someone who's never used Solaris or looked into its merits I'm curious: can someone comment on why all the nostalgia for Solaris?
For some Solaris has been one of the first UNIX experiences, as it was one of the most popular unices out there. Most university used it before Linux became popular. For others, like me, who learned Solaris fairly late (2006), Solaris was a testbed for one of the best operating system technologies out there. Modern filesystem (ZFS), dynamic tracing (dtrace), containerization (zones), dependency management during boot…
"Get 'em whilst they're young" - I doubt it was an intentional strategy for Sun, but it definitely helped their sales in the bubble.