BB tasks are anyways not proper competitive tasks, but they r designed to bring out the HMs latent nature.
Sree not doing the task or quitting them shows he's not at all sporting n is scared of losing tasks.
Dipika not doing tasks shows she's afraid of getting injured in tasks and isn't very dedicated towards it.
Deepak giving his everything in task shows he tenacious nature n never give up attitude, at the same time shows he'll go to any level to prove himself, which I personally don't like. Like he took maa kasam for the secret task. Shows his desperation.
KV in tasks shows his competitive spirit.
Romil shows how he tends to strategize during tasks.
So finally tasks do show the characters of the HMs, which otherwise they tend to keep at bay. Only thing is the narrative that BB goes along with regarding tasks.
In some seasons, they make it seem like task is paramount. In some season they make it seem like task is all about cheating n being a nastermind. This season they r saying that tasks r not the deciding factor.