It wasn't originally their product. It came with the Sun Microsystems acquisition. Sun themselves acquired Virtualbox close to selling to Oracle. Sun never monetized their products well, hence their demise.

Sun and SGI were once profitable but once Linux gained traction it was over.

They had no option to be assimilated by the Borg.

Cheap OpenGL hardware, from what I recall.

Ironically they were contributors to their own downfall.

That was a last-gasp attempt to regain relevancy. It really looked desperate, there was no real business plan behind it and the market could tell.

Your're missing their contributions to run Linux on their hardware, back when it wasn't seen as a danger to their bottom line.

I recall SGI were eaten more by Windows NT + off the shelf OpenGL graphics card than Linux. (But Linux also, of course. All non display output which was ran on SGI/Irix could be ran cheaper on Linux.)