Both card launched late september of their respective year (2018 - 2020)
According to Steam hardware survey:
In 2018 for Turing:
...... Nov/ Dec / Jan
2060..: - / - / -
2070..: - / .17% / .33%...
Early 2020 we had the usual trend of the decline of personal computer sales:
Q4 and total year:
Q42020 sales were 26.1% higher than in Q42019.
That give an idea of the pressure hardware supply chains must have, it is not just gaming PC/consoles that exploded, but regular work computer...