Agreed, So simple. problems occur if there is a gap between stem and plug, too much water, and when people MESS with them. Rockwool can be kinda tricky I think, holds so much water, but...
Dont listen to any of that. Your clones arent rooting because they’re too wet. Roots need to look for water.
Keep it simple. Get a tray, a Tall dome with vents, and one 25w t5 strip for seedlings. Cut clones, drop in a solo cup with ro water. When you’ve taken all your cuttings, pull them...