The smartest guys are in brisk period no one argues with out.
Now what’s a lot more important then being smart is actually learning itself not just growing your Payos and saying your in brisk now I’m not saying brisk guys don’t learn ofcurse they do some of the best massmidim our American Yeshivas produce are there.
But their is a portion of brisk that are just there to say I’m in brisk while doing nothing the whole entire day and yes their are mir guys who do nothing but mir is a 100 times the size then brisk and brisk is sopposed to be the best.
An average mir guy who learns all the time is learning more lishma then a brisk guy just because he not learning to say I’m in brisk and prove everyone he can learn better then you and is smarter.
My dira was half brisk half mir so I’m a pretty good source