Oh, come on, guys. It's not that bad!
Much of the criticism in the reviews and comments are based on purist sentiments about the character of Poirot as Agatha Christie created him, and resistance to any tampering with the worldview that Christie herself inhabited.
I thought Alfred Molina's worldly portrayal of Poirot was a refreshing change from the anal-retentive neurotic of Christie's imagination. The production was not that great, but a lot better than many TV features of its time.
While I love Agatha Christie, I have a huge issue with her worldview that the English born-to-rule gentry are unable to even respond to a doorbell without sending a maid to open the door.