#ReadLater is a personal thing, but if you have Community Tags turned on, when you search for #ReadLater, you see what's in everyone else's Read Later lists, not just your own. The only way to make this new feature useful is to turn off Community Tags.
This makes me worry that all of my personal tags are being shared to other people when they turn on Community Tags. Is this the case? That would be kind of weird. I use all kinds of tags like "Bought: 20201027" to mark when I bought resources and "Base: L7 Portfolio" to mark what packages I acquired resources in. I wouldn't want to be cluttering other people's Community Tags lists with junk like that.