According to our help center's page about the privilege to edit questions and answers:
Users are charged with the task of editing to improve their formatting
and content, recommending deletion if it doesn't belong on our site,
or marking that it is an acceptable post.
Recommendation to delete has a fairly low weight in our review system and it takes 6 such votes to delete the post. It takes 3 direct votes to delete posts with negative scores, and of course just a single moderator's nuke.
The review system is also built with a gradual increase of responsibilities of reviewers in mind, and allowing each member of our community to develop their own sense of what our site's standards of quality should be, as they gain privileges through positive participation. All of it is built with democratic spirit in mind and most decisions should, eventually at least, be reached as a community. In that sense, it is not anyone's right to suggest how an individual member's earned privilege should be exercised, moderator post notices notwithstanding.
So others can help you with technical issues, moderators can also monitor abuse of these privileges and remove them if needed (e.g. constantly voting by path of least resistance to gain review badges, targeted voting, and so on), but it's your decision if you should vote and what towards. If you think it doesn't belong on our site, vote to delete. If you deem it meets standards of quality this site should prescribe to, vote to keep. And if you can't decide, skip and/or use any of the other review options to address any outstanding issues with it (vote on the post, edit, flag, comment).
Should you leave any time for OP to respond to the post notice? No. It will take some time for enough members to vote to delete anyway, and moderators have agreed not to process flags on such posts too fast to allow their authors enough time to respond. Posts can also be undeleted if their authors ever edit them to comply with community requests and improve their quality, or if they otherwise indicate that they would like to (via flags, in chat or here in meta).
Also note that when a moderator adds a post notice, that doesn't automatically list that post in low quality review queue and a separate low quality flag has to be raised to do that, unless it's auto-flagged for low quality by the system for length or contents (spam, potentially offensive contents, too short to be likely of much use as an answer, and such). So if you were asked by the system to vote if it should be deleted, there is already some indication that it might have to be. But you were asked to decide when the flag was raised, not when a post notice was added to it. And the system already suppresses such flags for moderators for 15 minutes, so the community has at least that much time to decide on its own if such a flag is valid or not.