I assume you mean the range tool. Because IIRC it is possible to select non-contiguous ranges with the selection tool.
I agree it would be nifty to do this all at once by selecting non-contiguous ranges, but there are multiple workarounds for this with very minimal extra effort and while using the same tool the whole time.
You could assign a key command to split at cursor, then cut around them and drag them onto a separate track.
You could set the preference to use the mousewheel for event gain and crossfades, then split around the sibilant parts with a click of the split tool and attenuate them quickly
Or you could split either with the tool or with split at cursor and shift + click them all and edit like that.
Possibly all things you’ve thought about, and likely not as convenient as what you’re proposing. But I mean… there’s enough flexibility there that even if this was implemented it would be an upgrade but not a major one.