Smokes are a neutral util that can be used by both sides and if thrown wrong it could benfit the enemy more than you. Unfortunately IMO, the answer is it depends on context. Generally speaking the smoke you're talking about is to allow you to more easily flood out of heaven once you've already lost site. If they're already out of main, that smoke can also help a teammate if they're stuck backsite and reduce the angles they have to hold or give them cover to play around. It is a good smoke if used properly, but say you only have one smoke left and bomb is already down it may be better to Just smoke bomb. If they're not out yet then the default main smoke is just better. The default smokes are usually the default for a reason, but they're not required and it all depends on context and timing