In the January 2020 release of Collector there was the following new feature
Reuse Field Entries
Now you can easily reuse values that you previously entered into your form to minimize repetitive data entry and spelling mistakes. This can be quite useful when entering frequently used text such as a street name or Inspector.
Directly above the keyboard, in the keyboard accessory view, you can tap on “Recent Values” and find up to 3 previous values entered for that field to choose from.
Are there any plans to add this Survey123? This would be very helpful.