It's gotten to the point in other countries fans are actually ordering the product in English and then doing fan translations! I'd love to see them expand into other markets... many other countries and languages that the original was in that the remake is not (and of course not everyone got the same expansions so at least half the stuff is going to be new to them). But then I'm not in charge at Hasbro...!
There's nothing wrong with them slowing down development and just continuing to stock the old stuff. They could make videos highlighting great points of existing material, put out free quests on the Pulse page and in the app. There's lots of things they could do to fairly inexpensively promote their existing product, because a lot of people still don't know very much about it, but would buy it if they could! And so much spreads by word of mouth. You buy a set for your kids or your friends' board game group, and other people see what it could be, and may get their own copy, etc. Maybe one person has the game system and someone else brings an expansion over to play, so many things are possible.
They need to emphasize more how easy it is to mod the game and how many fan creations there are out there for free already. But they also need to expand. It's true, they can't just rely on a hardcore group that is going to buy each and every expansion as soon as it comes out, with no end in sight.
Thanks SteveRS2000 for yet another sighting:
https://goblingames.dk/tematiske-spil-2094/heroquest-jungles-of-delthrak-quest-pack-p52155