The three services are actually needed.
For what? If you say "to bring more windowsisms to linux" then I can believe it. Otherwise, not so much.
For applications. To handle properly when user changes the system settings.
These daemons are primitive at best. There were more comments written about them then there is source code lines in them.
Note, I'm in no favor of systemd itself. Debian in the past exemplified that you can actually use GNOME on a system without systemd, with only slightly patched up systemd-*d daemons. Which makes a lot of sense to me. But their maintainer is Poeterring, and he merged that all into the systemd, and there is no replacement for the daemons, so...
The usefulness of logind can be argued, but centralized management of date/time and locale changes were long overdue. Linux is pretty much the only OS remaining, where application, if needed, can't really know if/when date/time or locale has changed.
Unix (not so much linux) has for a really long time been a multi-user system, where multiple users can use different locales and different time zones.
Nobody dismisses the multi-user-ness of the *NIX. In fact, the services should improve that by allowing a user to easily change his own locale/time zone without the need for log-out/log-in cycle.
The blank the services are filling is allowing application to perform application-specific tasks *when* user changes the locale or time zone. Editing a text config, and then restarting everything is, sorry, but horribly outdated. (We can update kernel on the fly - but not locale!? WTF?)