As it is now, this setting is found under /admin/structure/views/settings
as a dropdown menu with only "hook_form_alter
or hook_form_views_exposed_form_alter
or adding a custom language and then "translating" that string
https://www.drupal.org/node/1319046 https://www.drupal.org/node/1520108
Lets improve this and solve another Drupal UX annoyance by making this setting configurable per view, per exposed filter, as a text field, with default value "Any" so that people can change that as they please.
Recent comments
Yes, this may be tricky. It's however easy to get comment data in a Content view: After adding the Relationship "Comments of the node" you will be able to choose fields like "Comment: Post date...
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Thank you very much! Looks great! A probably tricky add-on: Is it possible to also display new comments within this view? I mean not as a separate block or extra view, but directly...
User activity
Yes, this can be done with Views. I've rebuilt your second example with Views, see the following screenshot. Further below, I'll paste an export of the view configuration. Screenshot...
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