In spoken American English, it is very common to use the simple past tense as an alternative in situations where the present perfect would usually have been used in British English.
Many [most??] of these situations are the result of compressed speech with the 'have' being reduced to <'ve> then even further in faster speech where it becomes, almost to what sounds like or can sound like a totally unvoiced <'ve>.
There is also a distinction made between I've gotten
, meaning "acquired or come into possession of" and I've got
, meaning the same as I have.
The closeness of these sounds and meanings may result in a quicker death for the irregular verb form 'gotten'. Irregular verb forms are doomed to die because they are a vestige of a dead form of English. There are no new irregular verb forms being created because the rule for modern English is add 'ed'.