So you folks know about the old Tutorial Aspirations that are in the game (Trendsetter, Athlete, Chef, Painter), and that random townies can generate with them? I want to know if someone can make a mod that unlocks those four Aspirations to be selected when making a Sim in CAS. I know I'm not experienced enough to figure it out myself, but if anyone can do it, that would be very appreciated!

Requests are not allowed at MTS.
This would be the right section to reach out to learn how to make it yourself though I suspect these may have actually been patched out of the game / repurposed into other things, based on mentions that the traits they grant are attached to different challenges now, but your best bet would be to look through the tuning ( https://tdesc.lot51.cc/ ) to see if there are any usable remnants.

They haven't been, apparently NPCs still occasionally randomly spawn with those aspirations.

Fully unlocking them is obviously pretty trivial, so the answer of whether someone can is "Yes". But this isn't for requests. If you want to do it yourself, though, go for it. Just toggle the relevant classifications in the XML data and maybe SimData and it should work.

Understandable, thanks for your help you two!