Hi,
The following is meant as friendly offer of a complementary perspective, not trying to bust your chops, or to argue with the near-term focus on providing best data app experience, and I totally commend Streamlit for providing good pointers to community documentation about how to deploy SSL.
I’ve been acquiring, processing, creating, and distributing global data sets since the 1990s (for NASA’s EOSDIS) and I have learned to think about data as coming with a whole lot of intangible attributes attached other than just raw numbers. Most data comes into existence from its very first moment with  terms of use, privacy considerations, copyright and security issues attached (as well as inadequate documentation, and the need to update the data). I’m exaggerating, but just scribbling a few figures on a page of a lab notebook is enough to set those rights in motion. And irritatingly,  terms of use, etc., are very often a real and immediate constraint that prevent people from doing interesting and magical things with data. All those issues come with people attached who care intensely about them, and for all those people, having https enabled has become just one of many ‘table stakes’ items that are expected from people who are using their data and especially making it visible via a “data app”.  And roadblocks on deploying SSL are significant obstacles for those battling through them (I’ve done it dozens of time, but it’s always a headache).  I am sure I speak for many when I wish those roadblocks would just go away. 
I’m guessing that as Streamlit scales, the “soft” issues around data will become more important, and so will the outside-the-library deployment issues.  So my $0.02 is “put it on the roadmap!”