Absolutley quality video below. Shows how quickly an engine could/can actually be changed. To Be honest 2 mechanics can do a proper job in around an hour or so. This video does of course not take into account.
Items like Heater Cables (which are almost always seized) . The accelerator through the Fan housing can sometimes take 5-10 minutes alone if youve thin hands. Fitting and removing the fuel hoses can also be a right pain.
To do a VW Beetle engine swap on your drive with minimal tools and on an engine that hasn't been taken out for a long while will easily take a day.