My biggest worry with something like this would be data loss; some programs and web sites don’t have good autosave, so unexpectedly shutting down would risk losing work. Delivering a notification 20 seconds before shutdown would help by giving a chance to save; the challenge, then, is to make it so that overriding it is easy to do before the notification arrives, but hard to do afterwards.
(update: I had some data loss stuff during the pandemic because I started using some older/less advanced programs to do graphics and level-design for Gather Town. But I haven’t had the issue with most text editors or photoshop or whatever because of autosaving)
My biggest worry with something like this would be data loss; some programs and web sites don’t have good autosave, so unexpectedly shutting down would risk losing work. Delivering a notification 20 seconds before shutdown would help by giving a chance to save; the challenge, then, is to make it so that overriding it is easy to do before the notification arrives, but hard to do afterwards.
FocusMe can do this. Both give the reminder, and make it easy to stop before the time starts, and hard to stop afterwards.
FWIW I have never had a problem with this in 3 years
(update: I had some data loss stuff during the pandemic because I started using some older/less advanced programs to do graphics and level-design for Gather Town. But I haven’t had the issue with most text editors or photoshop or whatever because of autosaving)