When connecting to an geodatabase that is at a lower version level than the version of ArcGIS Pro being used, there needs to be a check that evaluates if the Arcade expressions being used are supported at the connected geodatabase version level. That way if someone is using a newer version of ArcGIS Pro than what the connected geodatabase is attribute rules that only have Arcade expressions that the geodatabase supports would pass the check and save the rules. But if the attribute rules have Arcade expressions that are not supported at the connected geodatabase level then have the save fail and an error message explaining why it failed.
Currently at ArcGIS 2.7 and ArcGIS Enterprise 10.8.1 you can create attribute rules that will save to the geodatabase without any issues but will cause the publishing of those layers to fail with Swizzling failed error messages in ArcGIS Server. Took me a while to figure out that the publishing error was being caused by one attribute rule that was attempting to return multiple values in one attribute rule which is allowed in ArcGIS Pro 2.7 but not ArcGIS Enterprise 10.8.1 so the geodatabase was not allowing ArcGIS Server to connect to the table that had the attribute rule.
