@David-TP 

Customers are obviously asking for this to be a feature, presenting separate SSID's, because its wanted and its necessary.

The problems and challenges that many customers are facing with devices not jumping or maintaining the correct channel could simply be prevented if the customer had this option and ability to control how the mesh rolled out in their ecosystem. In additiona, I believe TP Link would like to believe that 100% of the devices "automatically" only selecting the best network is the devices fault, which may even be accurate, but we can never know if we only assume the the mesh is always right and the device is always wrong.

I went looking for this feature because my Eufy cameras simply won't operate correctly with both bands on the same channel, even though they only support 2.4. I click 5g ban as not-available on my mesh and the cameras work 100%.  I want 5g to be available on my network though... so as a customer I must decide to scrap TP Link or do without 5g because of their ideology?

The bottom line is that customers want to present unique SSID's within their home and business networks for a variety of reasons. One of those reasons is to eliminate potential issues/problems with devices. I see this argument continuing in different threads and with different technologies/companies, and I hope TP Link will just take the higher road and give the customers what they are asking for instead of what TP Link wants. We happen to have a lot of TP Link switches and technologies and would prefer a customer prioritizing ideology! Thank you

 To everyone in this thread, my TP-Link Deco system now has the ability to add a separate "IoT Network" in a somewhat similar way to the initial "guest network" workaround.  This IoT network can be named separelt from your main ssid and set to 2.4 ghz only.  This has worked for 100% of my legacy WiFi devices and the original problem / missing feature of this thread.

  @jay_beast Can you confirm Hardware model /firmware, and app version?  I still can't see this on my kit...  (X73 1.0.9 / XE75 1.2.4)

a screen shot would be awesome.  

I have 3 decos:

A) 1 XE75 Pro as the main router v1.2.4

B)1 XE75 satellite v1.2.8 with direct line of sight to A)

C)1 XE75 Pro satellite v1.2.4 with direct line of sight to B) and connection preference set to B.  No direct line of site to A).

Especially after XE75 Pro 1.2.4 adding the connection preference so my 3rd satellite is guaranteed to use the 6ghz back haul - my WiFi throughout the house is amazing, and wired devices to C) in my study have near-hardwired performance. Prior to the connection preference setting C would connect directly to A with what I would guess is 5ghz due to the distance and lack of line of sight and devices wired to C had sporadic latency/ping issues. 

this is what the tplink deco app looks like where I can click into the "IoT Network" (or Guest Network is possible as well, but I actually like to reserve my guest network for guests) and set it up with a separate ssid set to 2.4ghz only.  My main need is for some early WiFi generation devices like a laser printer and lawn sprinkler controller that only allow 2.4ghz and break if 5ghz somehow gets into the mix with a shared ssid. 

  @jay_beast Thanks for that - the IOT option hasn't appeared in my app (v3.7.5).  I wonder if it's getting a region based rollout.... Also I hadn't spotted the connection preference option - I wonder if that's new.

Certainly looks like it might help with IOT config and management.... will be interesting to see if/when that feature appears in my region....

On my deco M4 I don't have option for IoT network...

@Zolteg 

The updates are applied via firmware rather than app updates, so check you have auto update turned on or check manually regularly.

@Zubr 

The M4 seems to be the real poor relation of the range.  I enquired of @David-TP a while back if the M4 would be updated. Like so many on this thread I was completely ignored, so the M4 have long gone.