At the moment our Silverlight suite is in maintenance mode - we do not include new controls, however, fixes of the existing functionality as well as highly demanded features are shipped with the regular releases of UI for Silverlight.
Regarding WebAssembly - for the time being we do not have any plans to invest in this direction, still, we will keep an eye on the project.
We are offering a variety of other products which can be used for your future work depending on your scope. If you are targeting the Web you can check our UI for ASP.NET , UI for ASP.NET MVC and Kendo UI products.
Do you need help with upgrading your AJAX, WPF or WinForms project? Check the Telerik API Analyzer
and share your thoughts.