I'm relatively new to Meraki products and researching new AP's for a wireless refresh. It looks like the WiFi5 AP's are end-of-sale and all of the new WiFi6 AP's have only 1 Ethernet interface. I'm wondering if the single Ethernet interface (no capability for LAG) would be considered a limitation when installing the AP at a location with 1G LAN infrastructure?
Note that the current crop of APs support multi-Gig (mGig) on their single LAN interface for the most part, so; 100/1000/2.5 - or even 5 Gbps, in the case of MR56. Uplink support reflects the capabilities of the installed radios and cumulative wireless data rate. Review the specific datasheets for full details.
Of course, you need mGig capable switching too, of which there are a number of choices, within our MS switch ranges.
The 2 ethernet port AP design was relatively short lived by Meraki and all Enterprise AP vendors. It predated mGig and offered a way to get a little more bandwidth to an AP. It also brought downsides: requires 2 cable runs =$, 2 switchports =$, and the AP only received PoE on one port so it didn't provide any level of resiliency should that upstream switch go down.
1Gbps is still sufficient to the AP in many deployments. As mentioned though most mid-tier and higher Wi-Fi 6 AP's include mGig. Pair that with a Meraki mGig switch (or any vendors mGig capable switch) and you have the extra bandwidth you need.
Entry level Wi-Fi 6 AP's typically top out around 1 gig of actual real world throughput and that's why you'll see them have a 1Gbps port. The higher end 4x4 and 8x8 AP's can have real world throughput numbers in the 2-3 gig range hence why we include either 2.5Gbps or 5Gbps mGig ports on them.
And it's a bit forward looking, but when Wi-Fi 6E comes out it will bring even higher throughputs and really drive the use cases for mGig switches.