Solaris is kinda known of doing various things differently, although still according to UNIX standards.
From Sun machines I have only touched some Ultra workstation, friend of me had bought two of them in eBay somewhere in mid-2000s (he was a big fan of SPARC as a CPU arch).
About truncating passwords - I remember Windows doing something similar in Windows 98 / Windows NT4 times. Or was it NetBIOS specific? Don’t remember exact details now.