I would phrase the second paragraph more like this:
A “ClassicPress research” project is one where the developer is permitted to use ClassicPress facilities to develop the project and to engage with the ClassicPress community. The ownership of, and responsibility for, a plugin (or other project) labelled “ClassicPress research” remain with the developer. ClassicPress cannot, therefore, be liable for any damage caused by either the plugin or the developer.
The point is that this goes much further than a disclaimer. No responsibility ever passes to CP, so CP can’t be liable. There is actually no potential liability to disclaim: all we’re doing is making the position clear.
It’s a bit like me owning a car park, where one car hits another vehicle. Unless there’s something deficient about the design of the car park or some directions I gave, that incident is nothing to do with me, so I can’t be held liable for it.
This is an important legal point. In many jurisdictions, limits are placed on what can be disclaimed. But if something never was a person’s or entity’s responsibility in the first place, those limits can’t apply because the person or entity never could be liable anyway.