You could be right about the
You could be right about the 150 A cap based on a recent Electrek tweet; however, it looks like the batteries on their 2020 Bolt EVs could have been cold-soaked. GM engineers have stated multiple times that they could have set the charging rate on the 60 kWh Bolt EV battery higher, but they chose not to (partially based on the limitations of the public charging infrastructure at the time).
Frankly, I don't buy the cooling argument. From everything I've seen, the 1 C limitation (set by the factory) on the Bolt EV's 60 Ah cells is due to electrode thickness. The Hyundai Kona Electric and Kia Niro EV don't have significantly better cooling systems, yet they are able to push the charging rate on their nearly identical cells to 1.1 C.
As for the charging limits, how were you gathering that information? And what year/release date Bolt EV were you tracking? My Bolt EV is the first release battery (I believe all Bolt EVs built after 2016 have a different battery), and both my Torque Pro readings and information displays on BTC Power chargers show 105 A after the initial step down.