When identity resolution links your browsing to your real phone number, it builds a behavioral record attached to your actual identity:
what health symptoms you searched at 11pm
whether you visited a bankruptcy attorney's site
how often you pulled up a payday loan page.
That record flows into the same ecosystem insurance underwriters, lenders, and employers pay to access. There's no notification, and no audit trail.
Fortunately there are some things you can do about it.