The fiction of the US filing their return on a postcard is not in the future, this despite the promises made by some key GOP taxwriters.
In truth based on the new tax law only a few lines from the current Form 1040 will be eliminated next year.
Granted many filers will not be able to itemize as a result of the larger standard deduction, they will still need to file a regular return. There are still the potential of Schedule B for interest and dividends, C if you have a business, D if you have capital gains or losses, E of you have rental properties of side businesses, F is you have that small piece of the family farm (there are a couple still out there) or the expanded child credit.