A quick update on the subject : I found 2 real life issues regarding this gating problem in Ableton.
The first one is not so problematic, but when you enable hiss in some analog emulation plugins, depending on the level of this hiss you may have no bloody output (when plugin is not processing). For exemple with the Fuse Audio Labs Flywheel.
The second one is more problematic : I recently tested the dithering feature in Limiter 6. Obviously, because of this Ableton Live issue, it's not working at all on low level audio (like reverb tails), where dithering is especially useful. Just export in 32 bit a blank audio clip with Limiter on it with dithering option enabled. Output is perfectly silent, instead of displaying some dither noise (of course I listened after adding some 70db of gain).
In 2024, when we have such powerful computers, I truly don't get how Ableton Live can have such an issue and still consider it as a feature...