NetWare 4.11 and 6.5 are included, but just don't have any screenshots on the site (the screenshots are not exhaustive at all and just a small sampling of what's there).

And even though there weren't very many 286 protected-mode OSes there were still several of them, with the OS museum including:

1B/V3 (a Japanese OS with an object-oriented desktop and extensive compound document support, part of the TRON project) Microport SysV/AT Prologue TwinServer (an obscure French OS that originated on 8080/Z80) Multiple versions of OS/2 1.x QNX 2.21 QNX 4.0 IBM PC XENIX

1B and TwinServer are especially notable since they were maintained as 286 OSes long after x86-32 machines had made 286 machines completely obsolete; the last versions apparently being in 1997 for 1B and 2002 for TwinServer (although the last version of TwinServer has some limited support for 32-bit code, it can still run on a 286)