I'm researching to see if I am autistic. One thing I come across a lot is childhood playing. What is meant by pretend play? Like, I pretended to be a "powerpuff boy", pokemon or Boxcar child a lot, and had a serious daydreaming problem, but was never able to pretend my dolls were actual babies or that the fake food toys were anything other than bizarre (except for those bottles that filled up & emptied those things fascinated me). I don't know. Is daydreaming only an allistic child's thing?
When specialist and researchers say that autistic children play in unusual ways they often mean behaviors like this: collecting, arranging/sorting objects (for example sorting pretty stones into groups), taking toys apart or studying how they are made, and playing with sensory things (like play dough, sand, water, etc). Typical play in their opinion is pretense play - children interacting with each other, pretending that their toys are alive or that toy food is actually edible, etc.
However that doesn’t mean that autistic children only play in one way and never do any of the typical pretense play - it just means there is a certain tendency researchers saw. It might be actually common, or it might be not as common. Some autistic children do both, or never do any of the atypical play. Personally I did both - I loved sorting and arranging Lego blocks or buttons, but I also played pretense with other kids.
Vivid imagination is definitely not only an allistic experience - many autistic people, including autistic kids, have vivid and colorful imaginations. It’s just sometimes imagination of autistic kids is different from imagination of allistic kids. For example an allistic kid might give their dolls or plush animals names and personalities and act out scenes using the toys while an autistic kid will make up stories in their head but not use toys or any objects to represent them. A lot of us continue to have a vivid imagination and make up stories well into adulthood.
So there is no universal autistic experience, but imagination and pretense play does not disqualify you for an autism diagnosis, and some types of playing behaviors are more common for autistic people and therefore can be an indication of an autistic neurotype.