How does the speed of a script influence polling frequency?
This is the reason that manufacturers publish datasheets for the parts they make.

All of your answers are in there.

A short summary:


If you don't read the data fast enough, samples will be lost.
There's a 32 sample buffer so that you don't have to immediately read every sample.
The chip can provide an interrupt output so that you know when it has data for you.
If you prefer to poll (or must poll,) there's bit in at least one message that tells you when there's new data available.  If you poll faster than the chip acquires data, then that bit tells you when you can get new samples.


Using all or any of those abilities may require additional setup (commands sent over the bus to setup FIFO, or an additional connection from the chip to your processor for an interrupt.)  All of that is in the datasheet.  Sometimes there's a lot stuff to know, and there'll be programming notes or application notes in addition to the datasheet.  Often times, the datasheets will include a reference to such additional information. Other times you'll have to go searching for it.