The main checklist view, as presented on the screenshot below, disappears (the view is rendered by Issue Checklist app, so once the app is removed, the view is no longer there):

When the Issue Checklist is uninstalled, the data is still available in custom fields (if "Save checklist data to Jira custom fields" option was enabled when the app was in use). It means that if you add the Text or YAML custom field to the View Issue screen in Jira, you can still see the checklist like this:

The data also stays in Issue Checklist external database for 90 days (as explained in Privacy Policy). After 90 days the data is permanently deleted. If you re-install the app before 90 days since uninstallation, you can still access the data