I don’t know how easy it is either, but there’s no lack of high priority work that might delay the feature addition.
Meanwhile though, https://www.duplicati-monitoring.com/ is seeking feedback, possibly even features like this.
In general, Duplicati has been providing raw output, then other contributors have been making it more useful.
Easier to read backup reports or weekly summarization
Client-side agent and centralized management / dashboardAnnouncing dupReport - A Duplicati Email Report Summary Generator
Remote Management for Duplicati
Announcing dupReport - A Duplicati Email Report Summary Generator
dupReport is interesting because it’s Python, like the tool you mention.
Let me send mentions to @crazy4chrissi and @handyguy (any others?) in case the idea fits their software.