I have experience in an internal IT helpdesk position. All I can say is that you are greatly overestimating the computer competency of the average person.
Your workplace also sounds like an exception in terms of competency.
Also, maybe you should ask the powers that be if they have to assign so damn many. I work in the finance/banking industry. We only have to do an average of two per quarter where I work. Enough that it's somehow possible to be 10 or more behind sounds absolutely soul destroying.
Then shouldn't the owner of the house be the one to make the decision? Not other guests?
I see no one calling for the removal of an existing trigger warning here. No changes to the status quo being requested. I see an asshole being a tool about someone making allusions that there should be a trigger warning.
Sorry to be pedantic. I'm generally supportive of your argument, but confused as shit because it doesn't appear to apply here.