Can i get a copy of my text messages with data copy request

No , you wont get a copy of text messages even you follow the steps in the article Get a copy of the data associated with your Apple ID account - Apple Support

As per this article Store messages in iCloud - Apple Support

If you use Messages in iCloud, you can easily set up a new device and access your entire messages history. Messages you send, receive, or delete are updated on all iOS devices, iPadOS devices, and Mac computers where you’re signed in to iMessage with the same Apple ID.

Note: Although your messages are stored in iCloud, you can’t see them on iCloud.com.

TMCrees wrote:

Can I get a copy of my text messages by submitting a request via data download

It seems no. Apple can't read them.

See >>> https://support.apple.com/en-us/HT208502