It drives engagement for his account. I doubt very much it's helping with user acquisition/retention.
Incidentally officials have acknowledged his 'neo-nazi ideation' though they've held off identifying a motive. If you peruse his online footprint it's rapidly apparent that he's been suicidal for years primarily due to a dysfunctional family background and difficulty in forming personal relationships. Right-wing ideology serves as explanatory framework/coping mechanism roadmap for a lot of lonely and dissatisfied young men, but the more the odds tilt against them the more likely they are to end up blackpilled. Arguably, some of the smarter/more manipulative figures in that movement invest effort in maximizing that, because martyrs make great recruiting tools.
https://www.theguardian.com/us-news/2023/may/09/texas-mall-g...