I think Catalyst is basically positioned as a stopgap for iOS developers to get something running on macOS, you can optimise it from there and later split out some code for a specific macOS target.
Yes, and this was my experience with the JIRA Catalyst app too. It's harder to implement new features in native apps, and it's a lower priority (on desktop) because it only affects one platform. So the project is deprioritized and never gets any updates.