Steven, it certainly isn't under WikiTree's purview or control, but something that is important is that profiles and FSPs for which members have used the internet Wayback machine as an archival method--of whom I'm one of many--probably need to be aware that all prior archival snapshots will now contain invalid URLs wherever links to Ancestry.com were used.
And as you note, not just instances where the templates were used: all links to Ancestry were previously made active with a prefaced code used by the Partnerize tracking system. Links that did not use the MediaWiki external templates are still intact and copyable as the full URL to Ancestry, but templated links are not. They won't be usable any longer unless people know how to search Ancestry using the numeric database and record IDs. This is somewhat more complicated to reconstruct when templates like the one for Ancestry shared images are used.
I've checked about a dozen Waybacked profiles and FSPs from 2022 through last March 14, and they show all links to Ancestry.com rendered as a URL with a prefix using the "prf.hn" domain, a name registered and used by Partnerize for tracking purposes. These are now invalid URLs. All links to Ancestry, presumably as of the fix of the recent problem, now point to "linksynergy.com," registered and used by Rakuten Advertising.
It's certainly no concern of ours if WikiTree chooses to change affiliate aggregator services, but I don't believe a global change that impacts all Waybacked archived data is off topic. In fact, I believe WikiTree should offer a general communication about the change.
GEDCOM exports really aren't a very effective means of backing up our own work since everything in the biography box, including all source citations, come through as plain text in notes fields, and there the use of the recommended external-link templates don't resolve to a link at all: they stay as plain text. To create a "live," formatted backup of a profile or FSP, there aren't many options.