We have a ticket status in JIRA called "Parked". It allows us to capture the feedback so the stakeholder doesn't feel ignored. And if we get repeated requests, we can find it, bring it out of parked, and it starts to become a real thing.

There is the issue of dupes but it avoids the other issue, which is that if you hard decline too many requests from right after they are submitted, stakeholders may stop giving you feedback, which is a bad thing. So it is an unhappy middle ground (which is I feel the normal place which product management occupies. I could setup a small shop in the unhappy middle ground and sell souvenirs.)

There are products for those like https://www.productboard.com/ or https://harvestr.io/

Tossing https://www.getcustomeriq.com/ in the mix - pretty much dedicated to this

Even in jira you can filter your backlog by issue type. (Not saying it's the best approach, separate project and links might work better, because the workflow is different).

Product management tools typically handle this. Jira Product Discovery and tools like Kitemaker keeps that information close to where the rest of the team works :)

Jira service desk to a separate backlog which is reviewed and filtered.