“Breuers I believe was the first American shul to start relying on kulos and doing Ma’ariv right after Mincha. I believe everyone else started when half of Monsey would pack into KAJ every evening.”
Anecdotally — it appears that in Israel most of the shuls i went to do not daven consecutively — even dati leumi. But maybe i just picked the wrong shuls.
I think that the pace of davening may have something to do with working/commuting. On Long Island the pace of davening (right or wrong) is dictated by the train. In our shul, we have four minyanim in the morning. There is an inverse relationship between how early and how fast. Minyan 1 finishes (on TWF) in about 27 minutes. Minyan 4 finishes in about 40 minutes. In Israel, as well it seems that shacharis takes longer (although it is a little longer anyway).