I watch alot of air incident reports on YT. Many of accidents (not crash) include words like "Unfortunately we wouldn't know exactly what happened, because pilots forgot to turn off the voice recorder after landing". Pilots become conviniently forgetful when some accident happens and it can possibly point to their mistake. Because privacy of two people at their job place is above safety of whole industry, you know, so others cannot earn on their expirience. I'd say, keep it at 2 hours, but suspend and send for training all the forgetful ones. OR, even better, make it impossible to open cockpit door after you have landed if voice recorder is still on. Make it a part of after-landing checklist. Make huge alarm siren. Make SWAT surround every plane until recorder is off. Anything is better then just waiving off the responsibility and potentially valuable experience