Putting it mildly, some people are upset. There are a lot of reasons; here I'm going to focus on people who are upset because we made a specific recommendation. What puzzles me is that some of these people would have been happier if we had withheld our belief that the review effort would be a waste of time. It seems misleading to withheld this information: the requester might well assume that we were supportive of the request but just wanted broader review. Such an impression would create great frustration when years later after review, the request was declined. There's an impression that by expressing an opinion, the IESG will not fairly follow the process should the community try to take a different course. Some seem unwilling to believe that if the requester did actually want IETF review the IESG would follow a fair process in seeking that review. I can understand the idea that if the IESG has a strong opinion it might get in the way of fair process. However that's true regardless of whether we actually express the opinion. It seems important to express such opinions; it seems important not to give people the false impression that they should spend a lot of time on a proposal without giving them realistic estimation of their chances of success. We need to find a way to do that without causing those who decide to go against our recommendation to feel that we are being unfair.
Another current frustration is the idea that the IESG is not part of the community. Particularly on process issues, some have expressed the opinion that when looking for consensus the IESG should be discounted. That seems dangerous: you don't want to exclude the opinion of a reasonably large subset of the people active in working with the standards process when deciding how that process should work. Besides leading to bad solutions, it is personally frustrating to be told that no, you aren't worth listening to. I realize it comes with the job. That doesn't mean I have to like it.