Dive bomb didn't have such a large aoe back then, the stuka dive could be easily dodged compared to the b4. You can still pretty effectively dodge the stuka dive. Pricing is also important 160mu on a starved faction to 90mu on a muni floating faction.
Could be easily dodge? Yea, when they rightly calulate time and drop bomb on my HQ, when my infantry retreats to it, reminds me "Dodge this" from Matrix. And in a midle of combat you can't always hear sound of falling bomb or if you hear it - it may be late. So, there is no differense between B-4 and Ju.87 in this.
And if pircing is important, then have in mind, that for to get that "90 muni" ability you should:
1. Choose that one doctrine.
2. Spend 600 MP (huge enough) for to get unit. Wehrmacht don't pay any MP for to call Ju.87. More than that - Ju is absolutelty unvunerable while bomb falling. Compare it with IL-2 bombing strike, which also costs way more.
3. Get Vet 1. That's not so easy with such random accuracy, like B-4 has.
4. Ok, now you are ready to snipe enemy units. OH SHI-, IT'S DIVE BOMB FALLING ON MY B-4!!!
5. GO TO 2.
So yea, Pricing is very important. But for B-4 you have to pay so much times more...