There is not a life-changing need to have an accepted answer in Recent feature changes to Stack Exchange, so for that case there is no need to have a "generic" account.
Also content posted on behalf of the company in Meta SE should not be "perpetual". If the user leave the company maybe the best is that post be locked, converted into a community wiki or copy/pasted as standard way to transfer the ownership of those posts to the current person in charge of the topic, if that is something that is still current.
Staff leaving the company or users that used to be staff might ask that some posts be locked or be unlinked from their account to avoid getting clarification requests or whatever on topics that they can not longer answer on behalf the company.
The need to have to change the accepted answer to Recent feature changes to Stack Exchange is an derived from using the Q&A model for doing something that is not a good fit for the Q&A on a site that is using a Q&A model that is not a good model for handling the interactions about the Stack Exchange network.
A "generic" account is a "sock puppet" account.
It might be good as an extraordinary short term exception in the mean time that a better way to track the features changes to SE.
But we should really ask if the current practice should be kept considering there are other ways to make an answer to stand over the others.
One option to accept an answer to make one stand over the others is to use formatting / content, i.e use Heading 1 or a nice banner only for the featured answer
One option to make it easier to find the featured answer is to add a link to the answer into the question.
Also users can sort answers by date, showing the most recent first.
The way that is currently handling in the current post, and in case that the the people involved in maintaining that post agreeds to use a sock puppet, IMO, should not be considered as a rule or bets practice to extended it to other posts in Meta SE or to be replicated other per-site metas. It should be discussed post by post, site by site.
Company / Staff
Regarding company announcements and other content posted on behalf the company that is something that the company should decide how they want to handle it.
I don't think that there is a "life-changing need" for a company sock puppet as there are tags for announcements among other standard features, as well there are staff only features that they could use without requiring dev time.
By the other hand it's possible that some staff didn't know about certain feature or that a post evolved into something different of the original intention. These cases should be handled one by one.
Posts on behalf the Company
I don't know at this time of any post made on behalf of the Company that might be better handled by a sock puppet account, that should be unlinked from the user account or should be locked, but I know about some farewell posts or posts announcing changing roles that might help to identify cases
Links that might help to find staff posts that might be good cases to review the convenience of using a company sock puppet account: