You're right that reducing pause times is made more practical here and this is a part of why people excited (and rightly so). That said, it's worth noting that

You're right that reducing pause times is made more practical here and this is a part of why people excited (and rightly so). That said, it's worth noting that a naïve attempt to free resources ASAP can be a performance hit and sometimes mean long pauses. For instance if you find yourself no longer needing a large tree, the regular GC lets you just forget about it. Freeing the whole tree would be walking the whole tree, and the naïve approach does that synchronously. Of course there are ways around that - they add some complexity, this kind of tooling will help get them right when they're needed. All in all, performance is complicated, there are usually tradeoffs, and this seems some great tooling.