Its good for cats to play with toys. It keeps their mind active and gives them confidence too.
Sure. That's why they make them. Toys keep them amused.
its always bad for them :D
if they enjoy it yes it can be good and fun for them.
Cats are vermin. Give them toys to play with if you wish to waste your money and their (limited) mental abilities. They will be out killing birds and rodents soon afterwards. Then they will be digging up neighbouring gardens to take a dump. Hateful animals in every way.
And my cat will find real snakes and plays with them, for this toy he does not play.
Of course it is good. Tthey need to put their energy away. And it would be better to do this with special toys not your curtains :)