In terms of implementation, these are recent changes events with rc_bot=1. Which would apply also to edits by "proper" bots, and those may be more important.

In the user preferences, "Watchlist" has an option for hiding bots, which controls what you see in the watchlist.

Email notifs however don't come from there, they are dispatched directly in core based on the "General" setting for "Email me when pages on my watchlist..", which is more stable than e.g. the current or last used setting when viewing the watchlist.

At glance it seems boolean, so it would likely be a product decision whether to want it in general or not. As James said, it might be a regression in which case it's probably an easy decision. Otherwise, I guess it depends on what established workflows may or may not expect.

I do note that Email notifs do have one additional setting. There's an opt-in to "also" get emails for "minor edits". That's technically separate from the bot flag, and the two are distinct and separate flags, but it might be a good one to hang it on to. Alternatively, we could come away from it with the notion that if a bot wants to avoid notifications that they should additionally mark things as "minor". However in my experience that's not commonly done currently, and one issue with that is that log events can't be marked as "minor" (e.g. mass page renames), and afaik maintenance scripts don't use "minor" together with "bot" either. That is however something we could change.

One issue with embracing "minor" as the way to control email is that it's not very transparent. E.g. the bot flag is hidden from RC by default, so it's clear that it has a certain effect. This isn't the case with minor on RC or watchlist afaik, so the only place where it is hidden by default is email notifs.

Change 778617 had a related patch set uploaded (by Krinkle; author: Krinkle):

[mediawiki/core@master] jobs: Add EDIT_MINOR to DoubleRedirectJob

https://gerrit.wikimedia.org/r/778617

Change 778617 merged by jenkins-bot:

[mediawiki/core@master] jobs: Add EDIT_MINOR to DoubleRedirectJob

https://gerrit.wikimedia.org/r/778617