I use a lot of very cool UI controls found in the Telerik UI UP control suite; our customers love these controls:

• RichText for HTML 5 presentation of email messages
• ScheduleView
• Diagrams - we use drawings for BP, WF and Data flows
• Docking - super popular
• Syntax Editor
• CardView
• SpreedSheet
• Expression Parser
• Expression Editor
• Layout control
• Expander
• Desktop Alert
• Transition Control
• TimeBar
• Wizard
• Window
• SplashSceeen
• Callout
• Drag and Drop Interactions
• Calendar
• Persistence Framework
• more..

You guys already know these capabilities don't exist as polished UI controls WinUI 3; we can't adapt and migrate to WinUI 3 / MAUI and lose these excellent presentation and interaction models. What other types of data and information would help your team to prioritize the development of these controls for WinUI 3. I know we can use some WinUI 3 UI control in our WPF apps, but going the other way is impossible. 

https://github.com/microsoft/WindowsAppSDK/discussions/465#discussioncomment-395712

Like many other technology companies out there in the wild, we aren't a UI Control development company as core skills focus on other technologies; however, we need the absolute very best 3rd part commercial grade and hi-fidelity UI controls to start with a base.  So for us, I'm not going to invest in a UI framework that turns the company into a Telerik - that's not what we do. Yes, we do develop custom controls, but it is the exception.