Except Plasma was never obsolete.It's always the same when something new arrives that makes old technology obsolete.
People that are invested in the technologie or the medium are going to deny the advantages of the new thing.
I just had a argument with someone yesterday about his 1080i plasma TV and he feels like there is not much available in 4k anyway and OLEDs are unnecessary and (Q)LED still can't compete with the quality of his plasma.
They simply quit pushing them as they were able to make far more profit on LCD TVs.
OLED, in my comparisons, really is not much or any improvement over plasma, especially at the huge price I paid for mine.
I almost feel a bit let down, I paid so much for OLED, and my old Plasma side by side, still held up.
I have all 3 types in my house, and the old 2013 Panasonic Plasma, still astonishes me, color wise, and overall clarity and detail wise.
They got forced out of the market, not obsoleted really.