Why did he do it?

He's a slav. Slav warfare is all about sacrifice. The first guy sacrificed himself warning the driver. The driver sacrificed himself, the passenger, and the vehicle to nullify the mine. The camera man lives to sacrifice himself another day.

All according to plan.

Why wouldn't he? If I were a Slav, I'd kill myself during even relatively good times.

combination of bein distracted and being up for days, i would guess

A group of bigots & trolls created a subreddit - /r/TransParentTransKids - where they could roleplay as transgender parents of transgender children, in order to platform hateful stereotypes of transgender people.

That subreddit has now been shuttered by Reddit for generally violating the Reddit Rules; They were engaged in promoting hatred of transgender people, as well as targeted harassment.

While doing so, they created posts that depicted sexualised minors and sexual abuse of minors.

The subreddit was created approximately two weeks ago but only picked up traffic in the past ~5 days or so, due to strategic targeting of harassment in order to promote public outcry -- including staging raiding their own subreddit from the /pol/ board of 4chan by "leaking" screenshots of the abusive LARPing to /pol/, inciting "outrage" and an influx of abusive activity.