We can see this market mechanism play out in the corporate lending market where companies with high credit risk must pay double or more interest rates. A debt jubilee would simply raise the default risk on all of society and thus increase rates to compensate.
I would think the bigger effect would be to dissuade lenders from lending more than the borrowers could repay before the debt forgiveness date. Also certain things that are inflated due to finance (like housing, cars, college) might see an adjustment to more affordable prices, or maybe some things would cycle, going up when people could borrow, and going down as the debt forgiveness event approached.
It's an interesting idea, to think about the pros and cons.
I also don't agree that a jubilee date won't increase rates. The default risk is simply much higher now and therefore the rates must go up to compensate for the added risk. In the current system, debt isn't forgiven when repayments are late, which allows for lower rates since the default risk is lower. If late repayments automatically implies default due to the jubilee date, then rates must be higher.
I look at it as mostly a thought exercise, questioning the way we currently handle debt. I think there is a lot of room for improvement. Maybe debt jubilees would act as a check on out-of-control debt, which seems to be a thing lately.
Take student loans. Politicians are talking about forgiving those debts. Maybe it's not such a crazy idea? But then again what they plan on doing will amount to just giving the banks the money, either inflating the money supply or treasuries that future generations have to pay back. Ugh.
Or maybe like in other countries, the price of housing would decrease to a three year loan instead of thirty.
Of course it is different in that it follows you around for a while, but there also isn't a weird enforced lending cycle (and carrying lots of debts into a jubilee might not officially follow you around, but it would follow you around).
Something like that could counter a lot of financial games that are played to the detriment of so many, which is why some societies had things like dept jubilees.