Wondering if anyone else is experiencing this or can confirm this. It appears as though the "Channel Width" column is no longer available when looking at the list of Meraki clients. We use that column occasionally to quickly see who is connecting to 2.4ghz vs 5ghz. I can't determine any other way to quickly find that information now that the column has been removed.
The column in question was specifically labeled "Channel Width" and it would show you whether the client was currently connected to 2.4ghz or 5.0ghz. The selection is still visible in a screenshot on Meraki's "Clients Usage Page Overview" KB article (link). It appears as though that selection was recently (last 1-3 months?) removed.
I don't recall ever seeing it specify exactly 2.4 or 5Ghz but based on the channel width shown you would easily be able to determine whether its 2.4 or 5Ghz as 2.4 only operates on 20 or 40 Mhz and 5Ghz is 80 or 160Mhz