I am not the author, but can speak as someone who has kept a "seemingly simple" semi-popular web service online for many years with no/low maintenance: it often comes down to the fact that issues tend to pop up just when you don't have time to work on them. It is usually not a lot of maintenance, but it feels like a lot when you have to dive back in to something that you haven't thought about in months. It ends up being a source of very low level chronic stress.

I can totally see why shifts in other priorities would make it attractive to decommission.