There are a number of issues with 802.11G, especially if more than one device is in use. Most devices are backward compatible with 802.11G which means they will work. It doesn't mean they will work well. 802.11AC is the best current standard and will work well with multiple devices. It will likely be superseded by 802.11AX in a year or two but that is a non-issue and AX provides little or no advantage right now.