That is a consideration, but you have to be pretty dedicated to running an alternative firmware on a router to even look into any of the Big Three (OpenWRT, DD-WRT, and FreshTomato) in the first place, so I'm not convinced that would be much of a factor.
I'm far more worried about developer inattention on commercially successful router hardware that is already widely distributed.
Suppose the BannanaPi project gets approved, and they distributed 10,00 of the devices - while Linksys's next product distributes 100,000 devices.
The project will be pressured to spend time on that which won't be spent supporting the Linksys. Result - while 10K devices will have openwrt on them, a potential for far more will be lost.
The problem in a nutshell is wifi6 - more accurately, the bugaboo/spectre of wifi6
the problem with building wifi APs is in the nature of wifi itself. There is no more available radio spectrum - go to any dense area and there's hundreds of wifi APs broadcasting - and (at least in the US) the FCC mandates that new wifi is not permitted to disrupt signals of existing wifi. So the new wifi chips are all compatible with the old ones - and will back-rev to the older protocols when they see those broadcasts - and the end result is not only is there NOT any new spectrum available, but the newer radio chips aren't any faster than the older ones. But wait - there's even worse. Wifi bandwidth is directly related to frequency - higher bandwidth needs higher frequencies - but higher frequencies go shorter distances. The newest wifi6 standards might go to a gigabit - but only to a distance of maybe 5 feet.
So the upshot of all of this is - you can drop $200USD on a brand new wifi router - and get ZERO throughput benefit over a 4 year old wifi router.
So from a hardware viewpoint how to companies like Netgear continue selling hardware?
They do it by lying to the consumers telling them the new kit is better than the old kit - when it's not.
Consumers aren't completely stupid so these companies do things like quit releasing firmware updates for 2-3 year old gear. That then forces people to discard old gear and buy new gear. Not so much in the home but it's really bad in the corporation - older gear won't pass security audits and so even though it's working fine it has to be replaced.
The Big 3 router projects really screw this up. By keeping 4-8 year old gear fully updated, it keeps that gear in competition with new gear the hardware makers release.
As a result the hardware makers have gotten nastier and nastier with releasing programming info.
Broadcom for example does not since they want to keep selling new versions of SoC's. And their consumers - Netgear, TP-Link, etc. - also want that and are no help pressuring them to release specs.
The only way to respond to this is by force. This is why the FSF was created - to use legal threats to help pry open specs from people who sell these SoCs and use free Linux software to run on them. This is also why OpenWRT is even thinking of screwing around with hardware. They think if they can get a hardware device on the market they will push how it's open with the thought that customers will clamor for open gear, and that clamoring will pressure companies like Netgear and Broadcom to tell customers that they will open their stuff too. This is why they are working with MediaTek - a company that competes with Broadcom - but has a much smaller market share. MediaTek opens its data to get customers who are demanding that and won't buy Broadcom.
The Big 3 are divided on how to respond to this. FreshTomato's response is just to keep it's head down, use the same kernels that the major makers like Netgear use, the binary blob drivers they use, and support a limited and older selection of gear. DD-WRT's response has been for their chief developer to sign NDA's with Broadcom for certain chips to obtain programming data allowing those to be used with slightly newer kernels, but unfortunately Broadcom seems unwilling to do this - yet - with it's wifi6 chips. OpenWRT's response has been to wring their hands and for a long time push users to hardware that uses MediakTek stuff.
The decision to try to compete head to head with the closed source SoC vendors like Broadcom and their customers like Netgear, with this BannanaPi project+MediaTek project, is for sure better than just the hand-wringing that's been going on. But I feel they are not fully utilizing the FSF's power. It's frankly disgusting when you open up a brand new commercially sold router and find OpenWRT in there along with a ton of binary blob drivers from the SoC vendor which make it impossible to use with the public version of OpenWRT. That's precisely why the DD-WRT developer split from OpenWRT so many years ago, he threw up his hands and decided half a loaf is better than nothing. The FSF should be pressuring these SoC vendors and telling them look, your silicon would be trash if it wasn't for Linux so the least you can do is open source the drivers for your older SoC's that aren't being used commercially anymore. They should be pressuring the router vendors to knock off nonsense like making boot loaders in these devices only load encrypted firmware (a regrettable development that has happened in the cell phone arena) without assistance distributing keys, like what was done in the x86 arena when Microsoft forced the manufacturers to release BIOS that would allow turning off secure boot and worked with Linux to get secure boot support in Linux. But OpenWRT seems unwilling to push the FSF to do this and has hit on this alternative of trying to compete in the router vendors backyards.
(out of ~40 devs) on the mail list so I believe we can consider the vote in favor of