Yes, it has been discussed in talk-cz, remove orphaned entities (I did it in the past, deleted about 2k orphaned nodes, see my history). About the mentioned object - not sure.- check it here http://ruian.poloha.net/19/49.98019/14.03835/ba . Pink buildings and red/blue address places are from goverment database (should be OK) and the mentioned building is not here. But if you turn on ortophoto, it is. The address place https://mapapi.poloha.net/node/10092644654 is wrong and should be deleted too. Correct address place is here http://mapapi.poloha.net/node/2352690396 or https://mapapi.poloha.net/node/2352688197 and in cadastre database https://vdp.cuzk.cz/vdp/ruian/adresnimista/5926467 and https://vdp.cuzk.cz/vdp/ruian/adresnimista/5925720 -. In CZ there are blue and red housenumbers with diferrent meaning. Not easy to say what is correct. Address should be removed and the building - who knows. Maybe exists, maybe not. I can;t check every (semi) automated edit if there are missing tags or it doesn't exist