What is currently on the table is simply a way to cleanly differentiate between closed ways that are polygons and actual closed ways. Example roundabout enclosing a park. The problem is that right now this relies on determining this from the tagging. This could well be implemented as a flag on the existing way type and not as an actual new datatype.

There is at this stage no intention to revamp the way how we model areas that are more complex than the single polygons from above, that is with multi-polygon relations.

The more controversial topic is giving OSM way objects partially or fully their own geometry.

The former would have for all practical purposes no noticeable contributor effect outside of geometry changes always creating new versions of ways, contrary to the current behaviour which can be somewhat puzzling for newbies.

The later would be quite drastic, but would provide more benefits for at least some kinds of processing, for others not, as then topology would have to be inferred.

In any case the 90% of the discussion on this topic fretting about tagging is completely misplaced as literally nobody is even remotely considering changing that.