While there is no specific way to provide feedback on moderators there are courses of action you can take if you disagree with the treatment you have received from anyone on the site, moderators included.
To paraphrase this post on the main Meta stackoverflow site:
If you have a dispute with a diamond moderator your options are:
- Contact stackexchange with your complaint and links to the questions/answers.
- Flag for moderator attention and request a specific moderator to address.
- Post to the site Meta (as you have done here) and ask for a response as to why your post was closed / deleted.
For the record. The levels of moderation on stackexchange are:
- Developers - Jeff and company.
- Diamond Moderators - Selected by community and listed in the About page of each site.
- 10K Moderators - Gained 10k reputation and access to moderation utilities.
Regarding your specific query on your question though, the main FAQ specifically mentions that questions that are rants disguised as a question are subjective and should not be asked (this FAQ is global for all Stackexchange sites so has not been written by any of the moderators on this site).
The question was closed for this reason. It also may or may not have been flagged for moderator attention so although it is only Rahul whose name is on the closure, if the post was flagged for moderator attention this is anonymous so details of who flagged it (if anyone) would not be made visible.
As for your point that questions are closed if there is no 'correct' answer available for them - this is not strictly true. There does not have to be a correct answer, but the question does need to be able to be answered. Again from the FAQ "Remember, this a Q&A site, not a discussion board."
As the closure notice describes:
As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or specific expertise, but this question will likely solicit debate, arguments, polling, or extended discussion.
Again, closure notices are not written by moderators, they are global for all stackexchange sites and help reinforce the suitable question format for this group of sites.
Finally, the main subject of your question - that you feel the comment itself was rude and shouldn't have been left. I reviewed that comment personally and was in two minds as to whether it should remain or not, but in the end decided it was a fair comment (if somewhat on the harsh side). In my opinion it was not rude, it just describes the issue he had with your question as well as why he feels it is not appropriate for the site. Not only does that comment provide useful feedback to yourself, it is also informative to other users of the site. For this reason I let the comment stand.
However, comments are not permanent and can be deleted at any time so whether Rahul decides to keep this comment is up to him.
Overall though, I am sorry if you had a bad experience with this question, and you are well within your rights to voice your complaints both here on Meta.UX as well as directly to Stackexchange themselves as detailed above, but I would like to think that you take the comments in the spirit they are meant because we do still want to help you with future UX issues you have, and I hope you can contribute to the site in future and that this issue doesn't push you away from the site.