I don't like the new icon with a dolphin on it and I want the old clean folder look back. Is there a way to do this? I looked around but couldn't find anything.
You might have to change icon theme/pack. There's tons on the KDE store and also probably packaged by your distro.
Personally, I am very much fond of the new icon. It's cute and adds a bit of character/whimsy. It's a breath of fresh air compared to all the flat monotonous design everywhere else these days