Well I don't think it mentions top 4 success, and there's no denying AM did win a cup, with an inferior club.
Even if all he does is steady the ship and keep us safe in mid table, the point that it's making about getting off AM's back is a valid one. The word Messiah doesn't appear in the article anyway. I was probably misled by this bit If that's not saying McLeish can do better than MON and if "great things" doesn't mean a trophy and/or a top 4 place it's just badly written.
Let's just settle for the fact that McLeish can keep the ship steady while RL slims down the wage bill to the level he now has the stomach for. Any temptation to generate support for McLeish by seeking to criticise the MON era, as I take this article to be doing, is divisive and pointless. Houllier tried that without much success.
MON was trying to do what RL wanted during his three seasons with us but Lerner now wants something different, so there isn't much basis to compare.