Do you know of any other publishing platform (either blog or newsletter or both) that does this?
Also try to find websites linked to what you are writing about. For instance, for articles about programming, https://dev.to/ offers a very good platform, and so does https://hackernoon.com/. Both guarantee that you completely own what you write there.
But to me the best solution is still to have you own blog. Many platforms will offer you a Wordpress or Ghost blog for a small amount each month (I would stay away from free platforms, most of them still own your content), and if you feel comfortable with a little tech steps, you can try a static blog generator such as Jekyll or Eleventy, and host it on GitHub or Netlify.
For my blog (https://scastiel.dev) I use Eleventy, hosted on Netlify, with my own domain name. Works like a charm :)
> You own the rights to the content you create and post on Medium.
> By posting content to Medium, you give us a nonexclusive license to publish it on Medium Services, including anything reasonably related to publishing it (like storing, displaying, reformatting, and distributing it). In consideration for Medium granting you access to and use of the Services, you agree that Medium may enable advertising on the Services, including in connection with the display of your content or other information. We may also use your content to promote Medium, including its products and content. We will never sell your content to third parties without your explicit permission.
> You can delete any of your posts, or your account, anytime. Processing the deletion may take a little time, but we’ll do it as quickly as possible. We may keep backup copies of your deleted post or account on our servers for up to 14 days after you delete it.
https://policy.medium.com/medium-terms-of-service-9db0094a1e...
Edit: compare with HN's terms:
> User Content Transmitted Through the Site: With respect to the content or other materials you upload through the Site or share with other users or recipients (collectively, “User Content”), you represent and warrant that you own all right, title and interest in and to such User Content, including, without limitation, all copyrights and rights of publicity contained therein. By uploading any User Content you hereby grant and will grant Y Combinator and its affiliated companies a nonexclusive, worldwide, royalty free, fully paid up, transferable, sublicensable, perpetual, irrevocable license to copy, display, upload, perform, distribute, store, modify and otherwise use your User Content for any Y Combinator-related purpose in any form, medium or technology now known or later developed.
However it's not fully baked yet, and not on a server that will have huge bandwidth.