The loose wheel yesterday was a freak accident. Rare, extreme circumstances. Indycar will look more at secring via tethers, I'm sure.
Major difference between NASCAR and indycar in regard to this kind of safety. Indycar the fence are/have been strong enough to keep the car within the catchfence boundaries for years now because the car is lighter. In NASCAR the fences have recently been upgraded after Carl's Talladega crash and Larson's Daytona crash. It's apples to oranges comparison in safety issues. In any imaginable scenario in indycar the car is light enough and breaks apart enough that major pieces piercing the fence would almost certainly not happen (not since Rennas test crash in 03'). NASCAR needed to upgrade their fences and they finally did, culminating with Dillon's crash at Daytona having as good of an outcome as you can realistically prepare for... better than Carl Edwards and Larson's crashes.
There's very little point in upgrading catchfences in indycar given the fences can already withstand cars impacting them. That's in regard to fan safety and fence integrity, at least. The tethers will be a cheaper/faster fix than fences, and that is for sure the route indycar will go.
I don't think NASCAR needs to do anything based on what indycar car does. NASCAR has always been more safety aware since 2002 or so, and they're wayyyy ahead of Indycar in safety even with all of indycar's advancements in the last 10 years.