I don't think BNB will overtake ETH, BNB have a goof improve but it's not anough because ETH is more popular and have a good platform and community.
These are different cryptocurrencies, and I do not see the reason for their competition right now. Although Binance attracts with the decision to burn their tokens regularly to support BNB, I believe that Ethereum has got better support. Take into account that most Dapps work oin Ethereum (they say, over 87% of them), so ETH is still better for many people than BNB, which is also a relatively new token.