It's disappointing to see one of the only MS trainings for LINQ that actually has you code a substantial amount yourself to be in such a pitiful state. Users need to install a dotnet tool that is really only used embedded in MS websites these days and along with that an SDK for an obscure version of .NET as well. It is evident from the other issues posted here that people are having mixed results, even with the efforts from the community to fork it into a usable version.

C# has a good reputation as a backend language thanks to LINQ. I would suggest to revamp this tutorial more in the style of recent Blazor tutorials and leverage the power of Github Actions or otherwise make this into one of those tutorials on learn.microsoft.com with the embedded code window that are available for the more foundational coding examples so people can reliably learn the code there.

There is certainly a lot of potential in the future of Blazor and Azure in combination with AI but to see, in contrast, an important training of one of the fundamental building blocks of C# in such a neglected state is truly very sad. Blazor apps will, in many cases, be leveraging EF Core and benefit greatly from the use of LINQ in that process.

LINQ has a bad reputation with regards to performance in some corners of the internet even though there have been plenty of improvements in that department over the years, not a single training that I have seen will emphasize / demonstrate that. I learned this from other developers. There is a lot to be gained by making a serviceable version of this training in my opinion. New developers shouldn't need Advent of Code or Bob Tabor's training from half a decade ago as their only source of inspiration to use this part of C#.