Bmx BB used to be common on hard core hard tails. The "bigger is better" mindset for bearings and axles etc with BB+crank. My le toy frame has a bmx sized BB and one of the norco 125 I owned ran a bmx BB+crank. Old school bmx cranks always seemed so tough compared to old school MTB cranks.
I wish all steel mtb dj frames had bmx bb’s. Profile cranks ftw!
So much stronger than aluminium POS mtb style, and all the front chain ring options from the bmx world. Super easy and cheap bb replacements. Love it.