I don’t think it’s worth the effort. To be consistent we’d need it for other apps too (roundcube, mattermost, etc.) but they may have different versionings.
IMO the advantage is minimal. You can check app versions in the different web UIs or on command line.
Some time ago @giacomo has maintened a rpm of nextcloud itself but the community of nextcloud did not raise effort to help nor to be interested to really use it. It ends that this rpm has been discontinued.
Darwin theory is not only for the evolution of species but also for softwares