You should contact the publisher first regarding the snap’s maintenance issues before bringing it up to the store.
Note that most snap publishers are doing their work as a hobby/side project, do not escalate this issue until sufficient communication effort is made.
In the meantime feel free to publish the snap using an alternative name, and request the store or instruct the user to set up a command alias using the upstream-preferred name.
Note that you can also request to become the snap’s contributor, which gives you administrative access to the snap while leaving the snap’s ownership intact.
You’ll need the original snap’s publisher to invite you from the snap’s backstage in order to do so.
FWIW I’d attempted to take over the snap gemini (to repurpose it for the LLM) in a similar fashion several months ago now, first by contacting the original maintainer if they’d be willing to give up the name via transfer and secondly via a dispute.
Months later, I’ve not had anything back from the store team beyond an initial “we’ll look into it” (and separately I can see someone else recently is instead going for gemini-cli and using an alias as an alternative, which isn’t problematic in itself but highlights a bigger issue here).
(Name of the employee hidden, likely not their fault after all )
I think if there isn’t already an established process for these kind of situations, there really should be. I remember several years back when Popey were still working here, he’d reached out from an admin capacity asking if I were willing to give up a registered name and I said sure. Reasonably in the same situation were I MIA, I’d have agreed with it just being taken by force.
There’s a fair bit of curation stuff I’d like to see improved, and this is an example of one of them, there’s no benefit to user experience in having multiple snaps doing the same thing whilst the preferred name is unmaintained and yet people can still accidentally use it over the preferred version, or to a similar degree (in e.g., gemini case but not OP here) - misrepresenting what the typical person would expect whilst also being unmaintained!
In this case for sqlmap I’d personally be keen on the ownership being transferred forcibly if the original maintainer doesn’t respond within a suitable time frame, these instances will only get more common over time and user experience is critical IMHO, it’s a slow boiling situation that only gets worse for users over time.
Which is to say 6 years later, I still agree with comments raised here from both myself and @Lin-Buo-Ren - people should be expected to respond to at least Canonical within reasonable time frames or risk having their snaps transfered (or hidden) in the public interest.