The sentence may work but it isn't grammatically correct; you'd need either all negatives or all positives.

It should be either:

... neglected at the cost of poor communication, inefficiencies and unreliability.

Or:

... neglected at the cost of communication, efficiency and reliability.

Personally to me the latter sounds smooth and the former still feels clunky. If they wanted to highlight the negatives it would be much better to phrase it something like:

... neglected, leading to poor communication, inefficiencies and unreliability.

Though I've generally stopped using "leading to" because it sounds like AI.