I don't think they really can. Larian has creative control over the project itself, Hasbro can't do much beyond input regarding DnD-specific things. Hasbro can try to milk DnD (as they have been doing), but this won't affect BG3.
This is an interesting question actually. From what I read, larian has been screwed by producers many times in its past, so they should be aware of these kind of problems. It all depends 9n the contract hasbro and larian have. And if hasbro is as stupid as Microsoft, larian probably has a favorable deal.
At least they licensed it to someone who did a good job and provided value instead of buying out the product that added value to the game they owned and then running it into the ground like they did with DnD Beyond.
Beyond stopped development when Hasbro bought them and the Encounter Tracker has been unchanged in beta for those years. They killed it by stopping development and flooding it with sponsored shit that gets in the way of using official stuff.
Killing doesn't always mean broken, sometimes it means lack of progress on useful features and drawing existing useful features in shitty monetization that makes it harder to use.