At first glance this seems to be the same as passing by value without the in keyword. To illustrate the difference, an example such as in the top comment of this post could be added. https://stackoverflow.com/questions/52820372/why-would-one-ever-use-the-in-parameter-modifier-in-c

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• ID: 6b1434b0-5459-7569-47f7-46bf33fc3953
• Version Independent ID: 8a4ae81b-1ae5-cbe6-d58b-df455414e245
• Content: in parameter modifier - C# Reference
• Content Source: docs/csharp/language-reference/keywords/in-parameter-modifier.md
• Product: dotnet-csharp
• Technology: csharp-language-reference
• GitHub Login: @BillWagner
• Microsoft Alias: wiwagn