I think the addition of the BSC "Binance Smart Chain" has certainly boosted the Binance ecosystem, with the high fees associated with trading on the Etherium ecosystem people have seemingly moved across and are making the most of the lowers fees. And even though the Etherium network would be more decentralised - I dont think people care - It's more about saving on fees to them that matters. And even with all of this I would like to add that if you look back - BNB has been one of the best performing assets in the cryptocurrency space - CZ is a smart guy who sees opportunity and pounces, that's why he's so successful.
Right now, it is more on saving fees rather than thinking that BSC is centralized platform. As many people are tired of high gas fees under eth, you can't blame them to look for better alternatives. If Binance will boost their marketing for this BSC network, in time, it will be a good competitor of eth network especially for those that are looking for other options and features.