ETH is stuck at too high a cost and tokens issued on the ETH platform are not welcomed by investors.
In contrast, BNB is doing their job well, most projects on the BSC platform are successful, especially those listed on the Binance exchange.
If ETH fails to solve the problem of transaction fees they will most likely be ignored by BNB in the race.
Even if ETH fees were equal to BSC, BSC would still have a significant advantage. Binance can provide infinite incentives to motivate users to swap to BSC from ETH.
ETH has no properties which cannot be effectively copied/pasted except for it's network effect. Binance has a bigger network effect.