In some challenging wireless environments, specifically those where you do not have 100% coverage, and especially those with a lot of concrete, leaded glass and other RF challenges – 5Ghz can be problematic. Some devices just love to hold on to 5Ghz connections even if the 2.4Ghz signal is better.
On your Meraki dashboard, it only gives an option to either run of Dual Band Operation (Both 2.4 Ghz and 5 Ghz band), 5 Ghz band only or Dual Band with Band Steering (detects clients capable of 5 Ghz and ‘steers’ them to that frequency, while leaving 2.4Ghz available for legacy clients). But no 2.4 Ghz-only option.
The truth is, it is possible, however you need to call Meraki Support to enable the option for you.
Not sure why they are not enabling this option by default. 🙂