As torok wrote in the second post of this thread, power whores hated last, very long generation during its last years, but it was a blessing for devs. This gen, with upgraded mid-gen units, can last as long or even longer and at the same time make also power whores happy again for some more years before they start asking again for a new gen.
So 2019-2021 is not an outlandish prediction.
And once again, everybody praise teh Almighty Analyst God!!!