I found out about Softimage XSI 8 years ago by accident. While trying to create a simple curved satellite dish mesh in a trial of Maya 2011 I was getting constant crashes, weird mesh behaviors and overall was in shock "how hard it was to 3D". I then turned to the internet in search of answers and... found out, everyone was having problems with Maya. Regardless of what you were doing, it was (and still is) a goddamn mess of a 3D DCC package. Particularly for a hobbyist. And especially after it going subscription-only a couple years ago.
I then started looking for alternatives. Tried Blender... Remember 2011 Blender? Yeah... Let me just say it didn't "click" and the UI as well as the overall flow of production in Blender seemed like something from a parallel Universe. Not the one I wanted to be a part of.
There was Modo and 3ds Max. Modo was kind of weird with its layer-based material creation workflow and was actually not that intuitive to model in (at least for me as a complete noob back then). Max was kind of cool. I remember doing stuff in 3ds Max in college computer class back in the day always finding its interface a bit archaic. I played with it for a while and almost settled, before accidentally discovering a post somewhere on the web talking about about some "XSI" app. There was a screenshot and the author was praising this "XSI" for intuitive UI, ease of modeling and animation as well as a powerful tool-set and even some cool procedural capabilities.
So I tried this "XSI" which turned out to be Autodesk XSI Softimage 2011 and... was instantly hooked! Yes, it didn't have VRAY integration back then, yes, Mental Ray was a pain to work with, but over time other renderers became available: Arnold, Redshift, nowadays there's even "Sycles" - Blender Cycles integraton for Softimage, believe it or not. As well as lots of plug-ins, ICE compounds, built-in dynamics and so on...
I was set.