The aphorism, "if the service is free, you are the product," is just as true today as it was back in the 1970s when the idea was first expressed about TV (before cable and streaming, TV channels were broadcast for "free" to all viewers.) The advertising-based business model of early television and radio has never gone away. Rather, it has become more aggressive, more specific, and far, far more invasive.
There are many "free" options for personal finance management applications. When you use these "free" apps, the currency you are paying with is yur data: access to your spending patterns, your cash-flow, and information about you are paying down debt, saving for a house, or living paycheck to paycheck.
When Mint shut down in 2024 and Intuit pointed users toward Credit Karma, years of end user categorized spending did not just vanish into the ether. Rather, the data moved inside Intuit's product family, alongside credit reports, tax filings, and business accounting tools.