I think those pages are showing the correct information. On article pages we show the last edited timestamp [1], and on the watchlist page we show the last modified timestamp [2] as the labels indicate. A quote from the documentation about the last modified timestamp [2]:

Aside from editing this includes permission changes, creation or deletion of linked pages, and alteration of contained templates.

The screenshots also confirm this - the last edited timestamp is earlier than the last modified timestamp in both cases.

If we decide to change this behavior, I'd like to know to what. Pinging Design and @JKatzWMF to see if they have anything to say.

[1] https://www.mediawiki.org/wiki/Manual:Revision_table#rev_timestamp
[2] https://www.mediawiki.org/wiki/Manual:Page_table#page_touched

It appears that you are right, as a null edit will change the time on the watchlist but not on the page. What is the value of that?

@kaldari, what do you think about ^?

@KHammerstein: Arguably, this is UX debt. What do you think about this?

@phuedx This looks to me like a bug on an existing feature. I think we should fix it but I'll leave it up to how you guys prioritize bugs.
UX debt would address new features or iterations on existing features, not technical bugs.

@bmansurov Oh I see what you're saying. Lets make them consistent. Should we go with last edited or last modified on both?

@KHammerstein, I think we should go with 'last edited'. I don't think many people care about the time when a permission changes for example.

In T100366#1386759, @bmansurov wrote:

@KHammerstein, I think we should go with 'last edited'. I don't think many people care about the time when a permission changes for example.

+1

@bmansurov @phuedx I agree

Hmm, I think, that a protection of a page should be visible in the Watchlist, too (btw. it's visible in the desktop watchlist). It's an important information for the editing community, just as an edit to a page.

Another kindof absurd example: if one is watching the page [[Chinese calendar]] the last modified time in the mobile watchlist is whenever someone last clicked the "refresh" link in the little box on the left, or the "purge" link in the Structure -> Day, hour, and week section. That doesn't really seem useful in any way.

Let's make it consistent with the date shown in the page, thanks for the input to everyone. Moving to next sprint.

Thanks for the report @Bp0.

Change 234705 had a related patch set uploaded (by Jdlrobson):
Be consistent in generation of last edited times

https://gerrit.wikimedia.org/r/234705

Change 234705 merged by jenkins-bot:
Be consistent in generation of last edited times

https://gerrit.wikimedia.org/r/234705