You are welcome.
If you deactivate a plugin on an entire column, you may want to deactivate it only on the locked rows. This is why you have the button to lock and unlock all.
Many users disable the plugins by post type and then use the Singles settings to change the settings on a few posts. I know this is not your case, but in that case, if you disable a plugin on the entire column you don’t want to lock all the rows because they would override the Post Types settings.
I know the padlock is sometimes a source of confusion, but it’s needed to assign the priority between Post Types and Singles.
In the Singles settings, you should see the warning “The Post Type Settings are overriding these settings for all the rows that don’t have the closed padlock”. This is how FDP tries to warn the user. Once the user knows the padlock is important to assign the priorities, I think it’s better to don’t lock all the rows when you disable a plugin on the entire column, but have the possibility to do it with the button “Lock all”.
If you want to be sure about the disabled plugins, you have the icon “?”. It’s the third icon that appears when you go with the mouse on the post name. Clicking on that icon you can check which plugins are really disabled. When you have doubts, click on that icon and you will see a popup that shows you the disabled plugins and by which settings.
What I can do is maybe adding a popup after you click on “Activate/Deactivate All” that asks you if you want also to lock the rows. Then, I think everybody would be happy ??