From what I have seen, a person either cares for scat voices (live or recorded) or they don't. Long time ago, I saw Sheila Jordon scatting live in Newport News VA and it kinda puzzled me at the time. I agree that scat voices tend to sound much better as background fills in styles than as solo voices.
Maybe I’m actually grouping too many voices under the heading scat voices.
It’s not just the doo be do bee’s,
for instance Surf Rock style you have a Beach Boys vocal sound in the intro. Same with Beach Rock.
Gospel intro’s you have a Gospel Choir . Soul Intro, voices also.
50’s Rock n’ Roll .
These voices probably existed in the T series? but certainly not in my S950.