Thanks for sharing the threads. I always think that downvoting is for discouraging bad arguments from DH0 to DH3 [1] (for discussion quality as you mentioned). Now I realize that even convincing arguments at DH6 can be downvoted as long as one disagrees with it.
I don't get it: do comments get downvoted on HN whenever there's any mention of or opinion on difference between genders? Disagreement shouldn't lead to downvote.
iOS has a Guided Access mode that does some/alternatives of what you said like lockout timer: https://support.apple.com/en-us/HT202612. I always use it when I let my kid use my iPhone/iPad.
This is similar to what I did too but the newsfeed is still polluted with lots of "likes" (e.g. liking a page, liking a post) by my close friends which are irrelevant to me 99% of the time. I wish Facebook let me hide "likes" from my friends.
Yes to me it is insane that Google doesn't provide native keyboard shortcuts (at least make it an option) for the search results page. It is available on Gmail, Google Calendar, Google Drive, etc. Why not Google search??
Google Search's keyboard shortcuts are so bad. I hope they learn from DuckDuckGo's. At least give users the option to navigate the search results with 'j' & 'k' like Gmail.