Lint In Drains
First of all ALL washing machines put a LOT of lint down drains including wringer washers, they always have.
90% of lint is cotton and is biodegradable, as is pet hair.
A WP bed of nails, GE FF or MT agitator mounted filters only catch from from 3 % to about 10% of the lint that a washer discharges into the drain.
The purpose of a washer lint filter is to catch the lint before it resettles on your clean clothing, NOT TO PROTECT DRAINS.
Common sense would tell anyone that understands hydrodynamics that a lot of lint being flushed out all at once is only going to help CLEAN build-ups out of pipes.
If you have a drain system that has serious problems it might be a good idea to use an old stocking on the end of the drain hose, this will catch ten times as much lint as the above mentioned washers lint filters ever would, and I would submit that it is far easier to throw away and old stocking full of lint than cleaning most washer lint filters.
John L.