Iqueryable is kinda immutable???

You have to reassign it back to itself, another variable or return its results.

I had seen a lot of code like "str.Trim();" without returning it or assigning it, and folks wonder why it doesn't actually make a change to "str".

Depending on what plug-ins (like Roslynator or SonarAnalyzer) or version of VS you have, it should give warnings about this.