I don't think it's passive aggressive. It could actually just be a mistake. I've emailed (admittedly much smaller) news organizations before when their RSS feeds went down, and received a response and a reinstated feed.

I wouldn't bet money on it coming back, but if this was an intentional move I might have expected them to replace the page with "Sorry, no more RSS, try our app!" or something. They are also still linking to the feeds at the bottom of many pages, like this one: https://www.reuters.com/tools/mobile/us

If nobody complains, then they'll know nobody really cares about it.

The passive aggressive part is the “(as though they’re not aware)” part of the comment. It makes it clear that the commenter thinks this is intentional but is acting as if it isn’t.

This entire post on hackernews. Likely the people who removed the RSS feed will read it.

Reuters read HN?

Some developers at Reuters definitely do. Indian and Belarusian programmers, heh?