Honestly I don't think a marketing team can do much about it. It's just extremely difficult with the playerbase they have to attract enough new players to make low and mid level content relevant again. You can see in the updates the last couple of years that 95% of development is done towards end game content. New people try to grind or leech to 200 to compete, losing interest along the way. Very few play the game as it was probably meant to be.
Another thing is the fact that many of the people that used to play during the "golden age" of Dofus simply got old, and quit for an array of reasons, most of them being boredom and real life stuff.
Well, there's literally no need to grind anymore these days. Kamas is worthless, items are worthless (unless you pvp maybe), and I can clear any content in my 2013 sets. I rush new content for the achievements and then log off again. Events just reward some more cosmetics or a balloon, nothing interesting. All the new cosmetic stuff is in theory a fun concept, but imo it's already worn out. What do I want 200 different shields for? Nobody changes looks that often or needs that many cosmetics, they only clutter my inventory.
I started in 2006, and I think 10+ years of Dofus is just too much for most of us.