Devkits have been software locked for a while now and need an always on internet connectivity to the mothership to work, so even if the HW kit would leak onto e-bay, there's nothing you can do with them as they would immediately be backlisted and usually that leads to the studio being blacklisted as well for the blunder so it's natural the studios don't want them to leave the office. You never know which disgruntled employee would rage-quit taking the devkit with him leaving you to deal with the wrath from the console manufacturer.

When I was doing some security evaluations on a gaming console it was mandatory to lock the HW samples in a vault at the end of the business day when the last person to leave the office was done with them. Naturally that made WFH impossible even during covid.