Hi Michael Remijan
Welcome to Microsoft Community
First of all, thank you for your support of Microsoft products. I also understand your regret about not being able to continue using the Microsoft product. Yes, you can refer to the following link:Use email to send notes to OneNote notebooks - Microsoft Support. In the section shown in the picture below, you can see that this feature was removed in March.
But don't worry, you can use the "Send to OneNote" feature as an alternative to meet your needs. You can follow the instructions in the link above or the process shown in the picture below to familiarize yourself with this feature, making your life more convenient.
At the same time, Microsoft is very willing to listen to users' voices to provide better services. You can follow the instructions in the following link: Ideas · Community, to try to provide feedback on this product change and help Microsoft better understand customer needs.
If you need any further assistance, please let me know!
Best regards
Hale.Y-MSFT | Microsoft Community Support Specialist