Yes, flatten the curve, as was done in other countries was the goal.
We failed.
European countries did not just reach a plateau and call it good. They made sure that the incremental increase in cases per day was very small - so on an overall plot of new cases per day, they actually curved down from where they were. In many US states, things were reopened when the new cases per day had plateaued. While that is an important step (you don't want a situation where the number of new cases each day is increasing over the previous day), simply holding steady only means you've started to cope with the problem. If your plateau is at 3000 new cases per day in a state, that doesn't really help hospitals that much, since we know the treatment timelines for Covid, once hospitalized, can take weeks. We need to flatten things by making the line that represents the total number of cases be as flat as possible - meaning very few cases are being added per day.
Following this methodology, European soccer leagues were able to finish their seasons (and are now playing the completion of EUFA Champions League) without any major outbreaks in positive tests among players/support personnel. I think there have been more positive tests among MLB players/personnel in the 2 weeks since restart than all of the major European soccer leagues combined.
US new cases per day rates were still high in many states when things started being reopened.
Also, a really low number where states don't have to worry about other states (which we have not had in place) would have really helped with trying to play football. How can we expect inter-state coordination on sporting teams when they struggle to coordinate on shutdowns?
In the end, a coordinated Federal plan (all states follow the same shutdown criteria, interstate travel is greatly limited - even intrastate travel is limited), coupled with better compliance by American citizens (wearing masks) applied for 6 weeks or so would likely have had us in a much better situation today. It would have sucked worse than the ~4-6 weeks of inconsistent partial shutdowns we went through, but based upon what we see in other countries, we most likely wouldn't be having 50,000 new cases per day 5 months out.
In the end, this is was a big factor that made playing football less likely.