My guess is cost and size. Those robots aren’t cheap and need a cell around them (the yellow device screwed to the table edge). To make it worse as they put a lot of weight on a small footprint you might need to locally reinforce the foundation. Additionally, the printer needs likely 2x or even more floor space compared to the build plate/print volume.
They do exist. For example, a maker space in southern Germany has one of those on display. Not due to it being practical but because they got their hand on a robot and tinkered with it.
My guess is cost and size. Those robots aren’t cheap and need a cell around them (the yellow device screwed to the table edge). To make it worse as they put a lot of weight on a small footprint you might need to locally reinforce the foundation. Additionally, the printer needs likely 2x or even more floor space compared to the build plate/print volume.
They do exist. For example, a maker space in southern Germany has one of those on display. Not due to it being practical but because they got their hand on a robot and tinkered with it.