I don't know about most, but it seems like many "not very high end" laptops from around 2015 didn't have 5 GHz.
My late 2013 mbp has it and I discovered the other day that it can actually negotiate up to around 1 Gb/s.
On the other hand, I have an HP ProBook 430 G2 lying around the office. I don't know when it was bought, but it has an i5-4210U which according to intel was launched in Q2 2014. So the laptop must be from late 2014. It has a Realtek RTL8723BE PCIe wifi card which doesn't know about 5 GHz. It works acceptably well otherwise.
My late 2013 mbp has it and I discovered the other day that it can actually negotiate up to around 1 Gb/s.
On the other hand, I have an HP ProBook 430 G2 lying around the office. I don't know when it was bought, but it has an i5-4210U which according to intel was launched in Q2 2014. So the laptop must be from late 2014. It has a Realtek RTL8723BE PCIe wifi card which doesn't know about 5 GHz. It works acceptably well otherwise.