Does “arbitrary decision making” imply one of these points:
(See Page indexing report - Search Console Help)
On the pro side of adding all these ?page=… canonical urls to the sitemap:
It gives Google a strong hint on <lastmod> for these url. Thereby Google has no reason to re-crawl unchanged ?page=… urls and might use its precious crawl budget for more important urls.
If ?page=… urls are missing in the sitemap, Google finds them anyway and does some “arbitrary” re-crawling - even if it’s totally unnecessary as there are no new changes to the content.
See Build and Submit a Sitemap | Google Search Central | Documentation | Google for Developers
Google really keeps track and makes a difference of where it knows about urls from:
“All submitted pages” (sitemap) or “All known pages” (links etc.)
See Google Search Console → Index → Coverage Report
- “A sitemap is an important way for Google to discover URLs on your site.” see
- “Google chooses the canonical page based on a number of factors (or signals ), such as […], presence of the URL in a sitemap, […].” see
- “Using a sitemap doesn’t guarantee that all the items in your sitemap will be crawled and indexed, as Google processes rely on complex algorithms to schedule crawling.” see