How can I remove unneeded (decom) Thin AP ?
Wireless controller details : Aruba
ArubaOS (MODEL: Aruba7205), Version 8.10.0.2 LSR (84367)
HCO version 2023.1.0
On the Cisco's, these disappear by themselves but for Aruba try deleting the decom'd AP from the Aruba database. Hopefully then it will also disappear from Solarwinds.
community.arubanetworks.com/.../viewdocument
As @superfly states - you need to decomm (aka remove) these via AMP or if you don't use AMP then via the controller CLI.