by default, the SEO Title field has a regular expression validator that prohibits these and other characters from the title.
You can modify (or remove) this regex validation by going to Administration -> Settings -> Advanced
From there expand to ContentView > Controls > FrontendPages
You need to update this setting in both FrontendPagesCreate and FrontendPagesEdit (so that you can change existing page titles if you wish as well)
These sections are the definitions for all the fields, controls, dialogs etc for the Create/Edit screens for pages.
Navigate to Sections > SeoSection > Fields > SeoTitle > Validation
Here under RegularExpression is the regex string used to validate input. If you know regex you can modify or create your own screen to limit characters, or simply delete the string entirely to allow any character.
Be sure you're in the Validation node, and not the SeoTitle node. The SeoTitle node has its own Regex property, but this is used to fitler
out these controls, which is why it replaces such characters with a dash - character.
Here is a video that might help on my Sitefinity Guru
Hope this is helpful!