I've been working on this problem for a while. Website upkeep is hard to quantify, but basically every disk fails and every operating system eventually needs a serious upgrade. The timeframe that a system can run continuously is not that long compared to the timeframe that information is relevant. So the most lightweight way to keep something up and running is to make it trivial to port to many hosting configurations by simplifying the toolchain needed to rehost it. (Note that humans are part of that workflow, if it's a company)
I've written a manifesto about making a commitment to keep websites online and maintained for 10-30 years, for people who are maintaining web content: https://jeffhuang.com/designed_to_last/
And on the flipside (from a user's point of view), I've also been working on a background process that automatically captures full-resolution screenshots of every website you visit, creating your own searchable personal web archive: https://irchiver.com/
I've personally been trying to make a commitment to keep my web projects and writing online for 30 years. My original internal goal when I started thinking about this, was to outlast all the content on Twitter, Google+, and facebook.com. One of those has already been met, kind of sadly.
I've written a manifesto about making a commitment to keep websites online and maintained for 10-30 years, for people who are maintaining web content: https://jeffhuang.com/designed_to_last/
And on the flipside (from a user's point of view), I've also been working on a background process that automatically captures full-resolution screenshots of every website you visit, creating your own searchable personal web archive: https://irchiver.com/
I've personally been trying to make a commitment to keep my web projects and writing online for 30 years. My original internal goal when I started thinking about this, was to outlast all the content on Twitter, Google+, and facebook.com. One of those has already been met, kind of sadly.