[quote="richb-hanover, post:1, topic:1018"]
I don't know the answer to this, but have some questions:
How old is a router that only has 4 MBytes flash? Can anyone say how prevalent are they?[/quote]
The TP-Link WR802N, which has at least some support, is still available. As I recall, when shopping for a travel device in 2015, that 4mb was prevalent in the market place and that the HooToo TM-02 (my first device) was one of the few that had 8/32. As I recall hardware improved in 2016 . About 1/3 of the devices in the ToH are 4mb devices. TP-Link seems to have the most devices in this class and also has CC 15.05 supported versions. D-Link is probably second and there is a variant of the NEXX 3020 with 4/32. I think that there is a very large population of a few specific TP-Links in the wild. The WR703 and MR3020 are two of the more popular versions. I would expect that the download statistics could help us understand the true popularity to the community, though we may want to look at this 60-90 days after the 17.01 release.
Not at all sure, but assume that build bots take up much of the effort. Again, looking at downloads for some extended period would shed more light on are we just spending CPU time building and disk space storing unused images.
Reading the posts it seems like those that can build an image with extroot can use the devices, but those casual (new) users that read a blog on "How to xyz" are probably are screwed, disappointed or both depending on the device and application. I agree that these devices can make a useful dumb AP and even a basic router for those than have minimal needs. Historically the Release image has included Luci, so for basic applications the previous should work. Unclear if there is still sufficient space for the USB components to config extroot (probably varies by device).
Trunk is a pain to configure on a single port device as the standard image by default has the Ethernet configured as LAN and no Luci. This requires more advanced skills and additional tools over a Release version with Luci and easy access to both the wireless config and package support in the long term. This post is also relevant. Installing LEDE on a router with a single WAN/LAN-port Models with a USB which makes them a bit more useful, but based on the posts noted here and on OpenWrt probably need a Release image with all the components to be able to run extroot compiled in the image (ie an enhanced default config).
Probably worth noting that the uneducated new user does not know that memory is a relevant specification or even to ask. The vendors usually do not include the specs for this (or the CPU in many cases), they just tout functionality. Image size then comes as an unexpected shock.
That said, I think it's time to sunset these devices, and probably plan a point a year or two after to follow with the 8mb devices. Barriers to entry are low ($), and I think that development time should be focused on supporting product released in the last 2 years. That said there is a level of effort to clean up all this stuff which may not be trivial as opposed to keep the status quo.