Is this normal?

[Sinstrel]

Just to give another perspective here, the playstyle of a balanced team (having the tank go first, dps do damage, healer support) in low/unranked games may also be more familiar to primarily PvE focused players. As your team composition becomes more diversified, so must the strategies you adopt in a game. Without knowing any details of your games; if the full DPS team attempting to play as if they are a balanced team, then that could be a reason you see them losing most often.

If it is any comfort to know, you are not the only person who has thought this way and experienced this. This was a very common misconception almost every one of us had when everyone was just getting to experience the Crystalline Conflict mode first released in Season 1 ("how is my rag-tag team supposed to beat a perfectly balanced team with healers/tanks/dps?"). Many people indeed stopped playing after that, but some stuck around and learned the answer to that question.

Edit: If your post is mainly asking whether or not games will match you in "unbalanced" teams often. Then the answer is yes, roles have no no bearing on your matchmaking. However, if there are 4 healers in que, the matchmaking system will attempt to split 2 healers per team. The same is true for tanks, dps, etc. So it is likely that there were just no other healers and tanks in que, and everyone wanted to play DPS that day which resulted in the party compositions you experienced. Hope that helps