We can confirm that we're actively developing and updating Zorin OS and have no plans to stop.
Our current focus is on completing development of a direct upgrade method which will allow you to upgrade between major versions (eg. Zorin OS 15 to 16) and editions (Core to Pro) without needing to re-install the system. We're also aiming to release Zorin OS 16.2 this October.
The release of Zorin OS 17 – our next major version – is tentatively planned for the second half of 2023. You can visit this page to get more information about it: