While that is possible it has not reached Arch Linux stable - only then it comes to Manjaro unstable, from there it will bubble up to stable branch.
As of just now 2024-12-22T16:42:00Z the version available is
$ mbn info postgresql -q | grep -e 'Branch' -e 'Version'
Branch : archlinux
Version : 16.6-1
Branch : unstable
Version : 16.3-4
Branch : testing
Version : 16.3-4
Branch : stable
Version : 16.3-4
Could be that major versions is very close and upstream Arch has decided to wait out the storm.
| Version | Current minor | Supported | First Release | Final Release |
|---|---|---|---|---|
| 17 | 17.2 | Yes | September 26, 2024 | November 8, 2029 |
| 16 | 16.6 | Yes | September 14, 2023 | November 9, 2028 |