This depends on how the site handles the user going straight to HTTPS.
If the site redirects back to plain HTTP at any point, then the SSL strip attack can succeed.
Some sites only enforce https for pages they deem sensitive, like the checkout. They may purposely redirect their users to plain HTTP for other pages. If they do, then the user typing https does no good.
When HTTPS is used throughout, all communications are encrypted meaning that any SSL strip cannot work.
To protect against users forgetting to use the https URL in their browser a site can set an HSTS policy to tell the browser to use HTTPS for a certain time frame (eg. a year). It is possible to get your site listed in browser pre-load lists so that HSTS takes place immediately rather than only after their first visit.