From the very source you linked–which isn’t even a good source to begin with since very little of the actual responses there use their cited sources correctly, often quoting shit out of context or misinterpreting the source material:

The “out of nothing” aspect of your question is more complex. In my personal view, and I guess that’s only an opinion, is that because banks are government regulated and insured institutions, forced to back each loan with reserves, and regulated to have capital for each of those loans, they cannot really be said to make this private money out of nothing.

But again, that’s just one user’s response. Not a credible source. So here:

Creating money

Banks also create money. They do this because they must hold on reserve, and not lend out, some portion of their deposits—either in cash or in securities that can be quickly converted to cash. The amount of those reserves depends both on the bank’s assessment of its depositors’ need for cash and on the requirements of bank regulators, typically the central bank—a government institution that is at the center of a country’s monetary and banking system. Banks keep those required reserves on deposit with central banks, such as the U.S. Federal Reserve, the Bank of Japan, and the European Central Bank. Banks create money when they lend the rest of the money depositors give them. This money can be used to purchase goods and services and can find its way back into the banking system as a deposit in another bank, which then can lend a fraction of it. The process of relending can repeat itself a number of times in a phenomenon called the multiplier effect. The size of the multiplier—the amount of money created from an initial deposit—depends on the amount of money banks must keep on reserve.

Banks also lend and recycle excess money within the financial system and create, distribute, and trade securities.

Banks have several ways of making money besides pocketing the difference (or spread) between the interest they pay on deposits and borrowed money and the interest they collect from borrowers or securities they hold. They can earn money from

•income from securities they trade; and

•fees for customer services, such as checking accounts, financial and investment banking, loan servicing, and the origination, distribution, and sale of other financial products, such as insurance and mutual funds.

Banks earn on average between 1 and 2 percent of their assets (loans and securities). This is commonly referred to as a bank’s return on assets.

https://www.imf.org/external/pubs/ft/fandd/2012/03/basics.htm

Which is a more detailed explanation of what I originally said. Yes, they create money. But it’s coming from somewhere and backed by something and not just magically imagined.

In the US, the Fed can just print money, and they have numerous times. But that’s because they’re legally allowed to. Banks don’t have the authority to straight up print new cash without something backing it up (e.g. reserves, assets, securities, transactions, etc.)