Senator Asks US Agencies to Remove Flash from Government Websites
While the end-of-life, security issues angle is a perfectly valid one I’m surprised this isn’t about accessibility. 
I would imagine government websites should provide information in an accessible way which Flash definitely isn’t. 
The recent HN post about the UK government moving from PDF to HTML[0] springs to mind as an example of a move in the right direction but given that it took a lawsuit to make laws publicly and freely accessible I think that isn’t a goal in US government somehow.[0] https://news.ycombinator.com/item?id=17541045