PSA: Sightstone is no longer optional
Everyone that got used to being a support and never building SS got completely boned with the new patch. There is no scenario in which a team without a sightstone has enough vision to compete with one that does, period. On top of that, supports are the only ones who can really use then new SS/income hybrid items, so 99% of the time you can't ask anyone else to do it either.
It sucks but it's absolutely true, and if you don't buy and use it you will lose whole games for your team.