At some point, if you have a user control component and/or have it stationary, you should fall back to VAMStory instead.
I don't know why we'd need a session plugin for that. I could add a "disable subtitles" flag in VAMOverlays, so that creators could add the option to the scene. But at the end of the day it would require creators to add that option and implement it in their scene ( and/or update older scenes ).
I optimized (at the time) the feeling and distance of the subtitles so that they are not to awkward in VR. But I'd say that the subtitle implementation comes down to the creator of the scene. I think the system is great for really short lines or "hud" alerts and things like that. Or eventually in very calm/short dialogs without other complex animations in the background.
But if someone is doing like a fully subtitled scene, with a lot of reading etc... this might not be a great choice, and should again fall back to VAMStory instead.
I had something in my mind that emulates a similar principle as Alyx (with the dialogs having a slight delay when you move around)... but since VAMStory also does that, I ended up not doing it.
If it's not for your scenes, and you have creators using this... you might want to recommend them to use VAMS instead with the follow option enabled.