That's not entirely the truth for "normal mobile devices".
My game works a lot better using crosswalk on my Samsung Galaxy S3 (4 yo phone, Android 4.4 only) than using Webview on Sony Xperia Z2 (2 yo phone Android 6.0.1), which is a lot better in all aspects.
If you have something like Samsung S6 or newer than you are fine... but not everyone can afford them. oh and btw. Android 4.4 and lower takes still ~30% of the market, which is just few percent lower than 2 years ago when A 5.0 was released.