I guess they changed their minds cause of all the people complaining about how that messed with counterspell.
I think this change is for the better. And it has nothing to do woth counter spell.
I hated the 4e format where every ability is "unique". Because they were not. Many abilities were similar but with little changes.
So with those abilties, you actually had to read the stat block very carefully.
If you read "fireball", you usually know how that works with no need to look it up at all. 8d6 damage in 20 ft radius.
The only information I might want is the DC. So listing it as Fireball (8d6, 20ft radius, DC 14) would be convenient.
For "healing word" the casting modifier is needed. So spelling that out would also be nice: healing word (2d4+5) would be nice.
Maybe they fear that if the spell is somehow nerfed later, the stats are wrong. In that case I would have been happy with
fireball (DC 14) and healing word (Cha: +3)
But yeah. That text is an abomination (I hate cross referencing)
Anyway I am more or less fine with the current form, but I do wish that Gold Dragon had it's Spell Attack listed, even if it's very easy to math out. (PB plus Casting ability so 16 in the case of the Gold Dragon)
I think that was just an error.
Creatures with spells that don't cast spells with a DC or attack list neither.
The empyrean has both values listed.
I think the Gold dragon was an oversight.