The emails have landed in my inbox, one every other day or so since Equifax revealed that cyberthieves had helped themselves to the Social Security numbers and dates of birth of more than 140 million Americans in the company’s files. And though the words differ (and some are unprintable in this space), the messages all end with the same demand: I want out. I want out of Equifax’s system. That company no longer has permission to make money off my personal data. I want them to delete my file and never start a new one.

It’s hard to blame people for wanting to quit in a fit of pique. This is an industry that uses our personal and financial data as its product, and the real customers are the banks and others who want to check up on us. And this breach isn’t like those at other companies that have let their data loose, like Yahoo or Target, where you can simply find another company to patronize. So, can you dump Equifax? And if not, shouldn’t you be able to?

First, some practicalities. When you sign up for a credit card or a mobile phone or any number of other loans or services, you agree — whether you know it or not — for the provider to send a report card on you to credit reporting agencies like Equifax, Experian and TransUnion. So let’s say you no longer trust Equifax to store your data in the wake of its breach. Sure, you could approach all of those providers and try to persuade them not to send data about you to Equifax each month. But it would be far easier to simply ask Equifax to erase your file and not make a new one.

But what happens if you need to borrow money in the future and you have credit files only at Experian and TransUnion? This poses an enormous problem when it comes time to make the biggest of all purchases — a home. Fannie Mae, whose rules govern the standards for many mortgages, wants information from all three credit “repositories,” as the company puts it.

There is already a potential out in the rules that allows for data from just two agencies if that is “the extent of the data available.” While this rule may exist to help people with a limited credit history, there’s no reason Fannie couldn’t also apply it to people with an extensive history that happens to reside only at Experian and TransUnion, and not at Equifax.

This wouldn’t be ideal for the mortgage industry, though. Credit reports tend to be riddled with errors, so lenders prefer a wider range of data to survey. “Lenders will compare the three and make their best guess,” said Pam Dixon, the executive director of the World Privacy Forum, a research group. “They kind of triangulate the errors.”

While it’s a nifty trick when an industry’s rank incompetence seems to necessitate a permanent triumvirate, a better solution might be a duopoly that actually cares about getting the data right.

Lenders who deal in smaller amounts seem flexible enough, and would have to become more so if more people had only two major credit files. American Express already is. It simply looks to the other two big credit bureaus for underwriting guidance if an applicant does not have a file at the third, said Ashley Tufts, a company spokeswoman. (She declined to comment on why American Express planned to continue to send data to Equifax, given the bureau’s now proven inability to protect it.)

Some readers, many of whom will have no need for mortgages or much new credit in the future, have tried to delete their Equifax files since the breach. One person sent letters making his demand to Equifax’s former chief executive, Richard F. Smith, before he retired last week. (The request received no reply.) Others have called the company’s various call centers. Often, they couldn’t get through or waited for more than hour and then spoke to someone who insisted that it was not possible to have a file deleted.

But what happens if you need to borrow money in the future and you have credit files only at Experian and TransUnion? This poses an enormous problem when it comes time to make the biggest of all purchases — a home. Fannie Mae, whose rules govern the standards for many mortgages, wants information from all three credit “repositories,” as the company puts it.

There is already a potential out in the rules that allows for data from just two agencies if that is “the extent of the data available.” While this rule may exist to help people with a limited credit history, there’s no reason Fannie couldn’t also apply it to people with an extensive history that happens to reside only at Experian and TransUnion, and not at Equifax. This wouldn’t be ideal for the mortgage industry, though. Credit reports tend to be riddled with errors, so lenders prefer a wider range of data to survey. “Lenders will compare the three and make their best guess,” said Pam Dixon, the executive director of the World Privacy Forum, a research group. “They kind of triangulate the errors.”

While it’s a nifty trick when an industry’s rank incompetence seems to necessitate a permanent triumvirate, a better solution might be a duopoly that actually cares about getting the data right. Lenders who deal in smaller amounts seem flexible enough, and would have to become more so if more people had only two major credit files. American Express already is. It simply looks to the other two big credit bureaus for underwriting guidance if an applicant does not have a file at the third, said Ashley Tufts, a company spokeswoman. (She declined to comment on why American Express planned to continue to send data to Equifax, given the bureau’s now proven inability to protect it.)

Some readers, many of whom will have no need for mortgages or much new credit in the future, have tried to delete their Equifax files since the breach. One person sent letters making his demand to Equifax’s former chief executive, Richard F. Smith, before he retired last week. (The request received no reply.) Others have called the company’s various call centers. Often, they couldn’t get through or waited for more than hour and then spoke to someone who insisted that it was not possible to have a file deleted.