Comment by jorvi

They are too conservative but it really depends. Lots of formal pants are a mix of wool, rayon and cotton. They'll indicate to only steam clean, and whilst they can be washed on 30c + delicate, you have to make sure to wash inside out and to dry them hanging from the legs. Mostly due to the rayon, although the wool is also a sensitive fabric.

In general it's just smart to wash and (air)dry things inside out. Keep the wear and tear on the inside.

And if you have decent suit jackets, pants or dress shirts, please just steam or hand clean them.