Ahrefs DR is just the most reliable one of the proxies we use to get an idea of the backlink profile strength of a site.
Because it's most difficult to manipulate (Moz DA is the worst in this regard, PBNs inflate it easily) and you can trust the value and its delta over time. It's pretty robust.
Majestic is decent too but I've seen enough strange results to only use it as a sidekick to Ahrefs DR.
At the moment it's the best thing we've got.
If you want to know if your backlink profile is headed in the right direction, Ahrefs DR is a good proxy.
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