Installing software via my web-browser is is one worry, but maybe my bigger worry is actually in cutting the distros out of the system.
Package maintainers are the reason I trust software to do things such as playing nice with my other software, that the licence has been verified, that the uninstall option will do what it should.
In "non-distro-ised" operating systems (which are all proprietary), the lack of these things leaves systems in a mess. I hope free software doesn't migrate to non-distro-ised ways of distributing software. The ability to add a layer of verification is one of the advantages we have over proprietary software.
It would be great if the extensions could be put into the distros. They could be grouped into a number of bundles if the number is too large. At times they might be months out of date, but that's still clearly preferable in my book.