Hi @maans ,
By default JCR, CQ and sling properties do not get rolled out.
I can see your properties name is jcr:countries. So for that you need to make changes in CQ MSM Content Update Action in configmgr

So in the above screenshot how I have excluded title and description similarly you can exclude your property here as by adding it here.
By default you will have jcr:.*
Update it to : jcr:(?!(countries)$).*
And now it will start getting updated on rollout.
You can also refer the below blog in case of any confusion
https://bimmisoi.blogspot.com/2020/08/page-properties-not-getting-inherited.html
Hope this helps!!
Thanks