Through /component/... link you can access any page of any Joomla component, but not only to Spagebuilder pages. This is how Joomla and its components work.
Therefore /component/ is hidden from indexation in robots.txt by default.
If Screaming-Frog defines these links, this may mean that:
- Screaming-Frog does not take into account robots.txt and is scanning backend links too
- These links are somewhere in the front (user error - do not use such links, publish pages through the menu item only)
- Bug of access to backend links. At least in SPPB 3, I have not met this. I have not checked this with SPPB 4, since I do not use it until all the main problems will be corrected.
I recommend downloading and checking your site through Xenu App. This will show all the links that are in the front-end and the pages on which they are located.