That's not strictly true. In Russia, unlike US or Europe, you have to show your passport to leave the country, and you can be prevented from leaving by court order.
This might be a valid statement for leaving the EU and US by land in some places of high trust (Switzerland, Norway) but certainly not a general rule by all means and certainly not by any other means (sea/air/train) where your passport or ID will be checked by at least the airlines and other companies (who act as deputies of regulations) and it will be matched against passport validity databases and other various databases (no fly lists, wanted criminals, interpol ...). And I know of several (if not all) EU countries where you have to scan/show your passport to access the departures gates in Airports (into an automated gate that scans it). Some even require such scan just to enter the airport since the last wave of terrorist attacks in 2015-2016.
I can absolutely assure you that in each and every European country the person leaving must show his/her passport.