I think the fear is the increased monetization will either be the wotc bison eating as many niches as it can, changing the beast into something that kills the tabletop plains or it will inadvisedly kill the d&D bison thus hurling the plains in the chaos.
I can't speak to people's fears.
I can speak to how there's rather more to it than WotC being a parasite. Even those who don't play WotC's games actually get value out of its presence in the community, and WotC gets value out of there being other games in the world.