A straightforward tool for everyone is not "behind" a comprehensive tool for experts just because it does less.
Minimizing the probability of someone using Task Manager to shoot themselves in the foot is probably more challenging than adding an advanced feature to ProcExp.
The "Details" tab on the current task manager is plenty for shooting yourself in the foot but it lacks features for power users. I personally think they just don't care.
Unfortunately, ProcExp started breaking with Windows 10 (columns regularly got into a broken state, requiring reset of the registry settings), plus they ruined the color scheme for the tray icons, so I switched to Process Hacker instead.