I'm not going to bother wasting my time on a point-to-point refutation on all the ways it's wrong, but suffice it to say it is completely wrong. Yes, the city is suffering, but not remotely to the degree portrayed here.
Based on conflicting information via google search, I'm guessing it's the sale transactions[1] that are down ~30% to 50% or more. Therefore, author mistranslated sales volume statistic into sale prices.
If sellers are not willing to lower prices but potential buyers don't want to pay because they think the properties are now worth less because of COVID, it seems that the logical outcome is less sales transactions.
[1] example story: https://www.cnbc.com/2020/07/02/manhattan-apartment-sales-wo...
excerpts:
>The total number of sales in the second quarter fell by 54%, the largest percentage decline in 30 years,
>The number of new signed contracts for co-ops fell 78% in June compared with a year ago,
>Signed contracts for condos were down 74%. Co-ops in the $2 million to $4 million range were hit hardest in June, with an 86% decline.