AviraDeArah,
“An eruv is a far greater concern. It’s allowing widespread chilul shabbos deoraysoh, not something which is a modern day decree designed to prevent a situation where factories are running on Shabbos etc.”
Actually, Rav Moshe never issued a psak din barur regarding Brooklyn. Furthermore, Rav Moshe admitted that his objections are mechudash. Hence, how can one argue that those who do not follow Rav Moshe are mechalal Shabbos.
