Yes if the Ancestry link is bad you can remove the link and changes to the profile. I would in a polite way by personal message or comment on the person's profile explaining that the changes and link did not work or show the information the changes indicated for the profile.
Here is a copy of a message I use about sources and links to paid genealogy site, you can edit it into your own words.
Links to sources on paid subscription sites such as Ancestry, FindMyPast, and MyHeritage can be frustrating for WikiTree members and visitors without access to these sites. We recommend searching for a freely available copy of the source document on sites such as FamilySearch, USGenWeb, Archive.org, and HathiTrust. If the source record is only available to paid subscribers, when providing the URL please also extract as much information as possible, such as relevant names, dates, and the source of the original data. Providing the source as an inline reference within the biography also helps to clarify which biographical facts are supported by the source citation.