I think this is the biggest thing about this.
No one can really say how good a job a CEO is doing. Their responsibilities are set by the owners who can choose to instruct them as closely as they see fit. For all we know, he's been making excellent decisions from day 1 and not being allowed to implement them. As much as it sounds harsh, Nelms has no responsibility to the fans of the club (aside from maybe making sure they don't commit any crimes).
My feelings are that the mistakes made on the footballing side of things are forgivable if they are learned from, you can try something out and then spend 2 or 3 years paying for that, no point wasting energy going nuts about that IMO. If they've changed their criteria and strategy, as Keyes and Nelms have said, that can be valuable long-term.
For me, I'd be much more interested to know what is going on with things like season tickets and general fan communication. I don't think that it's malicious but I don't think there is really a full understanding of the consequences some of their actions have. Football is an expensive sport and running things will always lead to contentious decisions but the approach we're taking leaves a lot to be desired and doesn't advance their own position in any way.