DY:
Nice try. You are a historian. We are in the midst of observing these two mesoros merging. A few examples.
* Just a single generation ago, an upsherin at age 3 was never found among the Litvishe community. Nor did boys wear payos. Only Roshei yeshivos wore beards. Colored shirts among baalei batim were the norm. Long malbushim and bend up hats were not for the average person. Today, these have all become the norm, to varying degrees.
* Just a single generation ago, the chassidishe communities were not interested in chodosh/yoshon, and there were very few kollelim in the chassidishe community. Today, these are norms. Chassidishe girls are as likely to seek “learning boys”.
There are still differences that are easily noted, but these are fading away. One can attend a chassidishe yeshiva, and hear as much about Reb Chaim Brisker as one hear about Chidushei Hari”m in Litvishe yeshivos. There remain levush differences, and the pronunciation of Hebrew is often different. But these have evolved much, and the process continues.
Who would have dreamt just 30 years ago that a Litvishe yeshiva would make an issue of white shirts during the week?