Yeah I'm not sure either. I played my character to level 3 as a rogue in 2e and then switched to 0 level wizard and worked my way up. My 5e version also has 3 levels. It gives great versatility but my spells are more lacklustre. I thought that was working as intended.I still don't see the problem with dipping.
In ADnD, a fighter mage was only 2 levels behind in both classes...
So dipping 2 levels of fighter in exchange for abilities, which will turn the wizard into a halfway competent fighter mage seems reasonable to me. NOT getting a subclass and one/two less feats and being a bit more MAD too.
I really don't get, where all the dippophobia comes from?
Dipping is a feature, not a bug. Getting strong features is necessary. It is just that those features may not be too strong.
Channel divinity as written seems to strong. Old Hexblade always was too strong. But those are specific problems, not general ones.