SRP is likely the most important aspect of clean coding. Bloated classes are difficult to test, hard to understand, difficult to debug, and hard to maintain. The well noted definition of SRP is worth repeating here; a class should have one reason to change. Having a class do only one conceptual thing provides a multitude of benefits.
Single responsibility keeps a class focused and much easier to understand and debug. After all, it has only one thing to do. New functionality should be added via new classes, not adding to existing ones. This can be thought of as separation of concerns as well.
Keeping SRP at the forefront of your coding approach will have far reaching benefits.