I agree that D&D will always exist, I am just personally uninterested in the direction the game is going with the OneD&D

I'd be careful with that. When D&D 3E came out, AD&D 2 wasn't cool anymore compare to other games, and many people weren't really playing it or heavily modded. Remember how everyone was playing Vampire in the00's and how nobody plays it anymore ?

It's very easy to change game, and many GM/players do every so and on. The question is whether more people move to D&D than from D&D. If they try to squeeze too much money out of D&D they can easily go in the more people leave. Well with D&D being above 50% market share even if they loose 90% of their player base, they'll stay a big name in the RPG world. However, would a company keep investing in a product were the revenue stream is falling (even if "still existing" ?) Investor tend to be quite pragmatic and when an product line doesn't make enough money, they tend to get rid of it.

It's messy with Hasbro, but it doesn't mean that it'll be good if someone sees that they can make more money through movies/video-games and paid VTT than by publishing good TT RPG