Created attachment 138784 [details]
Screencapture of the desired behavior with Dolphin and the current behavior using the Desktop applet

SUMMARY

When creating a new file, by right clicking on the desktop, the new file does not adhere to the sorting setting. Furthermore, creating a new file by right clicking on the desktop resets the sorting setting.

STEPS TO REPRODUCE
1. Right click on the desktop and click on "Configure Desktop and Wallpaper". Click on "Icons" on the left sidebar and change the sorting to "type". 
2. Create a new file on the desktop by right clicking on the desktop. 
3. Open the "Configure Desktop and Wallpaper" window and notice how the sorting setting is set to manual under the "Icons" tab.

OBSERVED RESULT

The newly created file does not respect the sorting setting and actually resets the sorting setting.

EXPECTED RESULT

The newly created file should be sorted according to the user specified setting.

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: 5.10.39-1-1-lts
(available in About System)
KDE Plasma Version: 5.21.5
KDE Frameworks Version: 5.82.0
Qt Version: 5.15.2

ADDITIONAL INFORMATION:

Note: creating a new file using Dolphin, respects the sorting setting. It's only when you right click on the desktop to create a new file where the sorting setting is discarded. Also, I'm familiar with C++ and I'm looking to get involved with KDE so I'd love to actually fix this issue myself if someone could point me to the right resources and source files!