Interesting you mention banks.
A 2019 study by Hua Sun and Lei Gao of Iowa State University found that from 1990 to 2015, same-sex couples were 73% more likely to be turned down for a mortgage than similarly qualified different-sex couples. In addition, same-sex couples who were approved for mortgages paid about 0.02% to 0.2% more, on average, in interest and fees.
https://www.investopedia.com/mortgage-lending-for-lgbtq-peop...
The US government has made positive changes to combat this practice,
https://www.reuters.com/article/us-usa-lgbt-banks/u-s-banks-...
but you would be mistaken to assume such discrimination has completely disappeared or doesn't still exist in similar forms.