Ron I think the answer for why no EXE is that the install of Sitecore 9 is more complex with more pieces. Now there are two IIS sites, the main site and the xconnect site, requires certificates to be generated and installed, there is the addition of SOLR which is its own install with its own certficates, and to try put all this in an EXE is very complicated. Well, the installation would fail often I think.
But to call the powershell install more easy than the old exe is silly.
To go further with example, Sitecore has made the exe type install better and more flexible over the last versions - you could pick what to call the website, you could move the SQL databases to new location, that kind of behaviour. Last week I had a reason to install an old version for testing and it was so easy! in comparison to Sitecore 9, where you can't even do the things like move website and database location without maybe edit the scripts. Sitecore 9 install is hard, but because all the pieces of it, I think that's why it is this way.