Why do I feel abandoned?

Thanks for the question, onesys01.

You can find the Windows 10 IoT Core open source BSP for RPi2, RPi3, Pi3 Compute Module, and RP3B+ here (https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fms-iot%2Frpi-iotcore&data=04%7C01%7CMichael.Bervell%40microsoft.com%7C345859be12e94df1e3c808d757cd7424%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637074412246612995%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C-1&sdata=Aye9YjIPWNHH05BJsGWiQhdZyX7N9on5tBrhxhWSKIQ%3D&reserved=0) for your use. If you are interested in expanding and supporting the RPi3B+ and/or Pi4, we would like to invite you (and the rest of the community) to do so in the open source rpi-iotcore repo! We continue to monitor GitHub and StackOverflow and are happy to help community development.

Additionally, we offer 10 years of support with Windows 10 IoT Core Services. You may use the open source BSP for Raspberry Pi, commercial BSPs supported by Intel and Qualcomm, or the recently released open source NXP BSP (https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.nxp.com%2Fdesign%2Fsoftware%2Fembedded-software%2Fwindows-10-iot-core-for-i.mx-applications-processors%3AIMXWIN10IOT&data=04%7C01%7CMichael.Bervell%40microsoft.com%7C345859be12e94df1e3c808d757cd7424%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637074412246617990%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C-1&sdata=trcqDqMVJTrnKETvlgHxKDNJJYtPlw%2FkIbbayyYikG0%3D&reserved=0), for which NXP offers commercial support as well.

Hope this helps!