As it is now, when you insert a date field it allows the visitor to input any kind of date, in the past and in the future. I think it would be very useful for many different use cases to be able tu customize the date range.
For example, if you are asking for a birthday, it should only be in the past, no use for dates in the future.
On the opposite side, if you are creating a booking form. The options should be only in the future, you can't book a meeting in the past.
And if you are making a form for an event for example, the available dates should be only between the dates of the event.
I think it would have many use cases and it's not that difficult to implement.