That's a tenth of all USA mortgages.
https://www.federalreserve.gov/data/mortoutstand/current.htm
https://www.federalreserve.gov/data/mortoutstand/current.htm
I can't do anything with a student loan. I can't sell my education. I can't discharge the loan in bankruptcy - something that could be done with a mortgage if I were somehow underwater. There's no way to escape it, and it mostly impacts the young who both have lower income available to deal with it and should putting away as much for retirement as possible.
[1]: https://fred.stlouisfed.org/series/HHMSDODNS [2]: https://fred.stlouisfed.org/series/HOOREVLMHMV
The exploitation of the old by the young is the bedrock of civilization. An "old person" invented the computer you post to HN on.