This was an intentional choice.
- It wasn't clear originally whether the basic tab will end up as a subset of the advanced. And while it did, we'd still like to explore e.g. merging cookies and cache datatypes in basic. (Since cache can be used for tracking in a cookie-like manner, e.g. with etags).
- We thought that users may be using basic and advanced tabs for different purposes.
- I have a vague memory of considerations along the lines of - syncing could have implied that a choice you made on the advanced tab is still valid on the basic tab, i.e. even if you don't see the other checkboxes, their state is still respected.

But I'm happy to revisit. If you think of the advanced tab as an expansion of the basic tab, then syncing makes sense. Assigning to Max if he had more thoughts on this.

I like the current behavior that allows to have two separate configurations that I can quickly switch between. 
But maybe that is a usecase that is only common if you debug browsing data deletions all the time ;)

Thanks for the summary, Martin. These are exactly the points that motivated our decision to keep the checkbox states separate. Another reason is that the items look different due to the different explanatory (secondary) strings so the connection might not be clear to some users. Especially because of the first point (possibility to merge items in basic tab) I'd suggest to close this bug (works as intended).

I was thinking that, if a basic option winds up aggregating two advanced options that are set differently, the checkbox on the basic tab could display as indeterminate, and then clicking it would set all of the covered advanced options to checked or unchecked.

I was actually hoping to use this theorized behavior when I ran into this behavior: I checked a basic option, then switched to the advanced tab to figure out which advanced options it covered.

Checked advanced options that aren't covered by any visible basic options should probably act as unchecked if the 'Clear data' button is clicked from the basic tab.