At this point it seems we can all agree that every single player of note on the team has been disappointing, in some context or another. So that ultimately points towards the coach (or, IMO), the whole front office. They've either picked the wrong players or put players in the wrong position to succeed. And in Horford's case he's supposed to lead but our two stars don't want to be led.
I think it's a lot to ask for Horford to just turn it on and off though. They put him in a bad spot, they run no offense through him, he has to play two positions, he gets benched. You'd like to see him make the most of this opportunity but some times you can't just flip the switch. And three-point % in particular is about rhythm.
Plus he's not an offensive star to begin with. A guy who only scores 14 points per game on average his whole career is gonna have 8-point nights and 20-point nights. A career 36% three-point shooter dropping to 32.6 in a small sample is meaningless. Either way he's not gonna explode for buckets. Not to mention it was the Lakers and there's barely anybody else they have to focus on defensively besides him and Harris (thus Robinson's performance).
You could have written these 10+ point losses to LA and LA in ink before the trip started, I'm pleasantly surprised they've shown up to the extent they did. Question is can they win at least 1 of the remaining 2, given they frequently lose to lesser teams on the road.