I didn’t say that England weren’t taking Pakistan seriously; what I said was that the Pakistan series were merely a glorified warmup for the main event of the English summer - the Indian Test series.
This series would define whether it was a good summer for England or not. If they win this series (which they will), no one will remember that England drew a series with a mediocre, 7th ranked Pakistan team. No one except Pakistani fans.
Similarly, had they won that series but lost this one, that win wouldn’t have mattered.