I keep seeing this talking point, but I don't think this was a speed issue at all. They had to ensure the physical ballot counts matched the bogus numbers from the vote tabulation software. They knew recounts would be happening so they needed these figures to match as closely as possible.

Remember, the vote counts were being switched from Trump to Biden, and in some cases being created out of thin air for Biden. We have not seen those numbers of irregularities with any other candidates as far as I am aware. Once the software had finished switching and creating votes for Biden, they knew how many fake ballots were needed. If they had voted for other candidates on these fake ballots, it would've thrown off the totals from all the other candidates' votes.

This is nothing new for Democrat strongholds cities. They have historically held back from reporting to see if they could find enough votes to win once the other districts had reported. This time, they relied on the software to do all those calculations to ensure they got the numbers right.