The reasons against it would go on forever, the reasons for doing it will not exist.
There is no way to keep from overpowering the bathroom fan.
There is no way to completely seal off the dryer air from the bathroom.
If your dryer is gas....
Debris (fuzz) pushed into bathroom, in spite of the possible built-in damper.
Bathroom air being pushed into dryer.
Personally I would find some way to exaust the air to the outside directly.