I doubt it's that. It has more to do with it being a no no to bash paying advertisers. I'm not sponsored. I payed for all my Vivosun gear and am very satisfied with my purchases. Grow equipment doesn't have to be expensive to work good. Tents, lights, etc... almost everyone is putting out decent products these days. Some just charge more. Same thing with nutrients. Some people spend a ton of money on them and don't do any better than the guy that spent $15 for a bag of Maxibloom.
I've had people tell me that I should have gotten a Gorilla tent because the frame is stronger, material is thicker, etc... The frame for the Vivosun is more than strong enough to hold what I need it to hold. I'm not doing pull ups with it which is something some always like to point out as if it matters which it doesn't. The material might be thinner than the Gorilla but it's thick enough to block out the light and create a pitch black environment for the night cycle. I guess I could have purchased a Gorilla tent for 3 times as much but that would not have made any sense. I'd rather keep that money in MY bank account not just spend it so I can brag about doing pull ups in my grow tent.
I guess I don't see anything to bash. Can you name something? How many of their products have you used that you were not satisfied with?