No, that’s standard. Literally standard operating procedure in most cases.
And actually, you can get 12 1/2 inch wide tires on a 7 inch wheel. We used to do it all the time.
Problem is nowadays, most big tire stores won’t do it because it’s not within the tire manufacturers recommended rim width.
If you can find a small shop that will do it, then you can make that happen. It’s not optimal, and to some people it looks out of place.
I don’t mind 33 x 12.5 tires on the 7 inch wheel, and have done it in the past. When going off road it protects the rim edge and also serves to keep the tire bead seated at lower air pressures.
For the street you might have to play with air pressures a bit, but it might still not fit the look you’re going for.
Again, tucked in is tucked in, and those wheels are always going to be shallow looking because of the offset.
If you find a wheel, that’s 8 1/2 or 9 inches wide, then mount your 12 1/2 inch wide tires to it, they might rub on the inner edges. Certainly on the front radius arms when turning
There’s a lot of fiddle farting around when you go to a tire that wide on a Bronco.
I assume your body is fully cut and flared? Or are you running stock wheel well openings still?