I heard back from that team. Here is their response:
Before we release a new SketchUp installer, we always run it through VirusTotal. VirusTotal uses dozens of scanners including BitDefender, AVG, Kaspersky, and McAfee just to name a few. We have a clean bill of health for this installer and would only release it if that were the case.
Furthermore, we always find a few false positives that could be system dependent or AV scanner dependent. We have filed a report with the Microsoft security team regarding the finding that has been noted in the two forum posts. To resolve this, you can disable Windows Defender during installation of SketchUp. Please let us know if that doesn’t work. If you really are concerned, you can also run the downloaded installer through the VirusTotal service.
You may report false positives with Microsoft. The guidelines for doing so are at;
https://www.microsoft.com/en-us/wdsi/filesubmission.
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