In 2006, an contest was held to create an original icon set for Haiku to replace the BeOS R5 icons. With the passage of time, much of the content surrounding the event has rotted away, including images of the proposed icon sets. Luckily, the Internet Archive has backups! The Stipi icon set won, with Honey, zuMi and Mc Clintock trailing close behind.
A post on the mailing list states “We Haiku developers agree on the fact that Haiku cannot be officially released with the original BeOS R5 icons. For this reason, all icons within Haiku need to be original artwork.”
Oh sorry I was misleading - that’s not what I meant. There used to be several icon sets for beos, like the ones here https://imgur.com/a/7dA4Qsk. Some of them came with install scripts, so you didn’t have to change each filetype individually.