They've attempted to kill off java several times. It's been second graded for years now in development. Geyser became a chore, using bedrock for java isnt fun anymore(it ran so much smoother, i kinda miss it). The list of bedrock exclusive features keeps growing each patch.

Not just the streamers, Java's community is massive thanks to Bukkit, Spigot, Paper and the like. They know that dropping java would just result in a fork to a clone. As the majority of the Minecraft community infrastructure is not dependent on Mojang and Microsoft.