Wrong the problem is they spent to too much time and resources on a pro scene that failed to produce new players.
While games like fortnite pump out skins and dances and crazy new additions that keep players hooked.
The pro scene is a money sink. The people giving Blizzard money were left with nothing to buy because of the money sink.
It was a huge mistake for Blizzard to start a pro scene so early in the life of a game. They should have sunk all that money into skins/cosmetics/new maps and crazy heroes. Get people to invest their money and they will become dedicated players.
If the player base gets large enough and the resources are there then maybe you can invest in a pro scene. A pro scene will always be a huge risk since the gaming industry jumps from fad to fad. Games get boring and people move on.