In AV-Comparatives’ July-October 2020 Real-World Protection Test, Microsoft performed decently with Defender stopping 99.5% of threats, ranking 12th out of 17 antivirus programs (achieving a robust ‘advanced+’ status).
As mentioned, Microsoft Defender is now looked upon as a much stronger contender in the free antivirus world than it was in the past, something that’s clearly reflected in the latest evaluations by the major independent labs that regularly test antivirus apps.