The only time toilet paper ever causes a problem in septic systems is at the Baffle , IF it Bunches up, which theoretically can happen at any time,, just bad luck
.. Trust me I have had to make myself an expert on this in the last 2 years , as NEITHER the Roto Rooter guy NOR my Septic tank Pump Company could solve my recurring problem, the septic guy only agrees to PUMP the Tank , which he did 2 times in a year .. obviously NOT needed the 2nd time as you can guess as my REAL Problem was in the BAFFLE area , which is under a separate Access point ( cement lid) that needs to be dug up.. usually 2 feet from the main access Hole .
Point is , it does not matter how Biodegradable the paper is if it ever BUNCHES up in this Restricted area which by design makes a 90 degree turn straight down .. Once its clear , the problem is solved , until it happens again, which is why some Homeowners install RISERS for quicker access..
Now If you use the " Baby wipes" you will be just BEGGING for this Problem . They are NOT designed to be Flushed , EVER .. Don't care what the package says.
They seem to be a Cash Cow for Roto Rooter Plumbers .. maybe they have some secret agreement with the Baby Wipes industry.. lol
The Leach Field is a whole different Topic, and if that is compromised you got major problems, usually that is not the case though.