If the market is flooded it will take some time and usually when there's a pump in the market it's expected to be longer though 1 - 10 minutes would be enough depending on how much fee you put.
He is talking about single block confirmation, so the state of the mempool doesn't matterBlock confirmation time is pretty random, like the person above said, sometimes it can happen within one minute of the previous confirmed block other times it can even almost an hour
The expected average is 10 minutes so every 2016 blocks, the difficulty is adjusted so that the block confirmation time is with in or at least close to the expected average.
Look at the most recent previously confirmed blocks
