OnAudioFilterRead is designed so that the audio thread gets attached to the scripting thread and is therefore susceptible to GC interrupts. There is ongoing work to fix this with a new system, which we have started releasing incrementally in 6.3 that addresses this design flaw, so we don't foresee us fixing this issue. See this discussion thread for more information: https://discussions.unity.com/t/audio-status-update-q3-2025/1681867/
And thanks for reporting!