Although there isn’t currently an option to rotate images when you preview them online, you should be able to apply changes (including rotating them) by using a third party app either through your web browser or when you access the file locally through the desktop app or the mobile app.
In any case, I’ve passed your comments along to the dev team regarding this and moved your post to the Share an idea section of the Forum, so as to keep track of your feedback.
Let me know if you have any other questions!
