I don't think it's as good as you say. If the recording released by the Pakistani Ministry of Defense is true, then the Rafale fighter jet's RWR didn't even detect the approach of the PL15 and was shot down.
I don't know much about electromagnetics when talking about the active stealth you mentioned, so I may assume that
1. The Rafale fighter cannot interfere with different radiation sources in the same direction
2. The active stealth of the Rafale fighter has a reaction time delay
3. From the classic radar formula, it can be obtained that there is a difference between the radar wave reflected by the Rafale fighter and the radar wave received by the J-10 fighter, and the Rafale fighter's active stealth cannot bridge this difference, so it was discovered by the J-10 fighter.
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