"mean" is far more useful to estimate how many transactions are likely to fit in a block.
Nobody said that it wasn't.
Are we all supposed to wait as long as segwit takes to make a difference. (which will be ages or never)
Hyperbolic nonsense, nothing surprising there. If you want additional capacity, you will try to use Segwit as soon as possible, otherwise you are indirectly stating that you don't need/want it. It is as simple as that. The calculations have been done and we can expect a realistic ~180% capacity after some time (certainly not "ages or never").
segwit is not needed today. It has just been sold that way by core.
2 MB block size limit is not needed today. It has just been sold that way by Hearnia & co.