The situation is not nearly as dire as you think. The problem you have is solved by WorldWideWeb. More specifically, by W3C HTML5 and ISO MPEG-4.
Preserving documents is what W3C HTML5 and ISO MPEG-4 are for. It’s why they exist.
HTML5/MPEG-4 are not just to enable you to share your documents across space, but also across time. That is because the decoder for HTML5 is a tiny piece of software that is totally standardized and totally cross-platform and is carried forward into future HTML decoders. The decoder for ISO MPEG-4 is also totally standardized and is built into every single hardware device in the world that can play audio video, and will be carried forward into future MPEG decoders. (But wait, the MPEG-4 patents! They expire in something like 2022.) Both HTML5 documents and MPEG-4 media are served from a Web server which is a tiny piece of standardized open source software that sends the document over the Internet via standardized HTTP. So your HTML5/MPEG-4 documents will be readable by future generations, even if they are using HTML15 and MPEG-10.
There is also ISO JPEG for photos. Works just like ISO MPEG works for audio video, and for all intents and purposes you can consider it to be part of HTML5 and/or MPEG-4.
Notice all the instances of “standardized” in the above. That is in stark contrast to various kinds of floppy/optical disks, FreeHand documents, physical media, print media, HTML4 (has plugins,) HTML3 (is not Unicode,) Flash, Director, Word, Excel, PowerPoint, PSD, etc. etc. Those are all temporary formats. You can work on a FreeHand document all day, but if you don’t create an SVG of it and put that on a Web server, it won’t outlive you.
So whatever documents you want to preserve, create HTML5/MPEG-4 versions of them, and store them on a standard Web server. Also keep a copy on your current computer. Also keep a local backup of that computer. Also keep a cloud backup of that computer. Then move all of those copies forward to your next computer. The truth is, your floppy disk data should have moved onto your first hard disk, and then onto successive hard disks, and then recently onto SSD.
Whatever you are creating today, you should primarily be creating an HTML5/MPEG-4 version, and aware throughout the whole process that your Illustrator or Word or Final Cut documents are just a bridge to get to a final HTML5/MPEG-4 version that represents your actual published work. Same as a graphic artist in 1995 was primarily creating a print brochure, and was aware that the FreeHand document they were working in was just a bridge to that print document.
There is an issue with keeping the Web server containing your archived documents online in perpetuity, but that is more financial/logistical than technical. In theory, part of your life insurance policy could be dedicated to purchasing a T-bill that pays out enough every year to keep your Web server online. Or you could buy such a T-bill right now.
Some example media from the question and answers above:
graduate thesis or any text document (e.g. Word) ➡ convert it to a semantic HTML article
FreeHand file or any graphic ➡ convert to SVG graphic
print photos ➡ convert to high-quality ISO JPEG
print documents ➡ Web documents (print is obsolete now and has been replaced by Retina Displays and gigantic billboard screens)
VHS video, DVD (MPEG-2,) MPEG-1 ➡ convert to ISO MPEG-4 H.264
Compact Cassette audio, DAT audio, CD audio, MP3 ➡ convert to ISO MPEG-4 AAC
animated graphic (e.g. GIF) ➡ convert to animated SVG
interactive animation of any kind ➡ convert to interactive HTML5 animation (Tumult Hype is a great tool for this)
… the list goes on and on, because there is always a way to convert legacy media into modern HTML5/MPEG-4.
There is an old digital saying: “if you only have one copy, it doesn’t exist.” That covers the data loss part of archiving. You can’t put some data onto just one computer and rely on that computer not to fail or be stolen or lost. You have to make multiple copies to ensure you can actually get the bits off later when you want them. But there is also a second part to that: “if you don’t have a standardized document, it doesn’t exist.” So you can have 8 copies of a FreeHand document at 8 different locations, but then you try to read it and you don’t have a functioning version of non-standard FreeHand, so your documents also don’t exist. The standardized document formats are HTML5/MPEG-4.
So to put it all together: if you don’t have multiple copies of your document in HTML5/MPEG-4 format, your document doesn’t exist.
There is also one other archival issue, which is whether or not a future generation can actually understand your document. For example, if the text of your thesis reads “the test subject is 5-foot-4” then the vast majority of human beings who are alive today can’t understand those already-antique measurements, and even fewer of the next generation and the one after that will understand. In the same way we have ISO video and ISO photos, we also have ISO measurements. So you need to replace “5-foot-3” with “160 centimeters” and “32 degrees Fahrenheit” with “0 degrees” and “2 miles” with “3.2 kilometers” and so on. But that is true even if you are just publishing something on the Web today that expires a year from now. We also have ISO time formats (YYYY-MM-DD) and so on, which you should use in your document and then optionally, you can use scripting to localize it.
If you are skeptical for some reason, you can watch 13+ hours of 1980’s music videos on YouTube:
… which are being served to you as HTML5 pages with MPEG-4 video in them. Likely these songs and videos predate all of the media you are thinking of archiving.
Or a playlist of 1970’s music:
1970’s music hits playlist
… or let’s go back to the 1940’s via HTML5/MPEG-4:
Big Band / Swing / Jazz 1940’s
… or look at a photo from 1953 which lives on as ISO JPEG in an HTML5 document:
The Forces Show, 1953 (BBC Archives)
… or a Mac Plus which was hardware in 1985, but which lives on today as an HTML5 document:
Mac Plus Emulator
… it goes on and on.
So WorldWideWeb is full of old stuff that not only predates many of the people who are alive today, but also predates WorldWideWeb.