Well, they're thinking of overhauling the core.[0] Pablo Vazquez also made a video on why he thinks it shouldn't be 3.0 yet.[1]

[0] https://code.blender.org/2013/06/blender-roadmap-2-7-2-8-and...

[1] https://www.youtube.com/watch?v=iJE7vMmOYZ4

That roadmap is 6 years old at this point. I’d imagine plans have changed a little since then.