hkunnana,
IMHO it’s always a good idea to keep applications updated with new versions as they are released. Nextcloud is no exception since they are continuously adding features, improving performance and enhancing the user interface.
Changes with each version are documented in the change log and or release notes.
And the nextcloud upgrade process is really slick via the web interface and before you even start - you know if all your addons have versions that work with the upgrade. It’s very well managed.
So in short, yes - keep Nextcloud updated with both major and minor upgrades.