Agreed. Drew Karpyshyn was the Lead writer for ME 1 & 2. When Mac Walters took there was a quality drop.
Example: the Dark Matter plot line was dropped and, I seem to recall, this was meant to be the motivation behind the reapers. Creating a psychic species that could control dark matter.
ME books story series also crashed once Drew Karpyshyn left.
To be fair, it can’t be easy finishing off someone else’s work.