There are about 17,200 parishes in the US> The last time I went through and counted, there were less than 3% which had an EF. A number had the EF as the parish Mass (in other words, appear to be Ef parishes - SSPX chapels are not counted). They can be identified as they have the EF for weekday Masses also. Others had one Sunday Mass, some with a weekday Mass and some without.
Then we have parishes which have rotating EF Masses - in other words, not every Sunday.
Then there are some which have one or more weekday Masses (usually one) each week (such as Saturday morning). then we go to those which have it every other week or once a month; there was one in Oregon which had an EF once every 6 months.
Not all which have a Sunday Mass have it at what might be called “normal” time, somewhere between 8 a.m. and noon; a number of the Sunday EF Masses are some time in the afternoon. A parish near me has one Sunday at 6:30 a.m.
Interestingly, a priest who was very committed to the EF came out publicly in an article, stating that unless the Mass started to be said regularly more widely, it was in danger of fading away. Anyone interested in actually seeing what parishes have the EF can go to Coalition in Support of Ecclesia Dei; they seem to be updated regularly and include Canada, Guam and Puerto Rico.
Another comment comes from some research done by CARA (Center for Applied Research in the Apostolate). They indicated that the greatest attendance at Mass weekly, by age group was those over 50; it was better than 50%. The lowest attendance group was the 18 to 29, which if I recall, was about 18%.
So when I see something indicting that youth is going to revive the EF, I just say “Oh”. It is not worth arguing with some people.