It's ease of use with streamlabs (a must/default on streaming platforms), makes it the first thing people are reaching for when streaming.

I think the only concern is taking attention away from an opensourse solution when they could get more funding/attention to keep it current. Though I doubt it will ever go away, since once you deal with a crash or something weird with SLOBS you immediately go back to OBS.

Its OBS on training wheels, shiny pay for more shiny training wheels.