Is that still relevant in the light of this?:
Would heavily "depend" as to weather its beneficial to your forum to have profiles indexed or not and the ups and downsides of both instances.
For example, if all your profiles and registrations all filled out their profiles with nice rich content, used profiles like a social media account and added value and accountablity, then it might be worth while having markup showing which author is associated to which content.
But on the flip side, there is negatives to be considered in how many profiles are good and bad, and how authors are perceived across the web if they are identifiable with pattens.
Having thousands of thin/duplicate content from essentially blank profiles, imo causing a much greater impact forum wide than people realise.
And the usage of crawl budgets crawling parts of a site that offers little to no value, means that crawl budget isnt being used on priority and new content.
Same goes for blogs, It's only really beneficial to have author profiles if you have multiple authors of a good reputation web wide and/or you need it to show authority and knowledge of experts for Googles view on E.A.T and Yamll.
My opinion is that while I believe forums will have/are having a resurgence with the increasing volume of A.I generated content and Google scrambling to make "user generated content" a "thing" again. Authorship should be taken on a case by case basis of a particular site, like everything with Google and SEO, there isnt a one size fits all. What's good for one business, niche, website.....doesn't mean the same variables apply, especially with search intent playing such a role in how written content is perceieved.
