A shared university toilet can still be part of a house or low pressure system. I’ve yet to see public restrooms which had a lid for the toilet itself, outside of low pressure toilets in communal housing. If you can link to where they clarified the shared university toilet was high pressure, I will stand corrected.
It appears they studied a shared university toilet, likely not a common household unit. The further study that it references I found here
This is referencing hospitals, again not home toilets. I’ve yet to see any actual info on standard low pressure toilets.
A shared university toilet can still be part of a house or low pressure system. I’ve yet to see public restrooms which had a lid for the toilet itself, outside of low pressure toilets in communal housing. If you can link to where they clarified the shared university toilet was high pressure, I will stand corrected.