If it didn't have any substance it wouldn't have such a big competitive scene. Sure its not quite as technical as some FPS but it is more team based than a lot of FPS. In order to stand out in the multiplayer FPS crowd you NEED a good hook and Lawbreakers has absolutely no charm and its aesthetic is incredibly boring which is a major part of the reason its doing so poorly. Looks mean a lot when the market is so saturated. On the other hand PUBG is a fairly ugly game but its concept is very well pulled off and got a lot of people streaming it etc. It has its own hook just with its concept.
Saying Overwatch is not as technical is an understatement. If it wasn't for the 'charm', I think the game wouldn't have an audience at all.