Yes, Return Frequency can be used to show bucketed returns. But this won't necessarily represent "Logins".
Even if your site requires login, users would hit a login page and might bounce without login in, or your site may allow for long term logins, meaning they don't have to "log in" each time.. so I guess it really depends what your definition of "login" is - users on your site; users actually logging in (the actual action of logging in); etc...
If you are just looking at basic UV metric (regardless of the login status, or identifying the user based on a unique id/guid), then yes, what you showed can work.
You should also be aware of a few things with Return Frequency:
- Complete New (first time users) won't show in this report... a user must return to the site to show up
- The same user can show in multiple buckets... If I come to your site today, later today, tomorrow, 5 Days after that, then 16 Days after that - I will be in "Less than a Day", "1-3 Days", "4-7 Days" and "14-30 Days" buckets
You can also do a histogram using "Days Since Last Use Instances" which could create a nice visual