We will arrive from the USA at Dublin Airport at 9am on a July Monday morning. Is it likely we will have sufficient time to board the 11:15am bus from the Dublin Airport to Galway after our 9am arrival?
50/50. Sometimes planes leave late as you know; sometimes they arrive early like mine did from Dublin to Chicago yesterday
Two hours should be more than enough time to make it through immigration and get to the bus. But are you doing carry-on only luggage, or will you have bags to claim? Are you packing snacks for the bus row, or will you want to grab something at the Dublin airport to eat there, or to take onboard the bus?
We did it last September (carry-on bags), and grabbed seats up front on the top level of the bus, for the best vies all the way to Galway.