It makes things look more crowded, but unless people are actually using the Comcast WiFi it isn't actually adding to congestion. The periodic SSID beacons are an annoyance but they use negligible bandwidth. That said, don't ever use an ISP provided access point.
Regarding "inferior": It's fast enough and it doesn't crash (at least for me). That's probably "good enough" for most people to not care if there's a better solution.
"lack of control": The Comcast provided hardware gives me an IP via DHCP and I'm able to disable all those useless firewall features. So which features am I missing and why should I care about them?
I have quite a bit of networking knowledge and also used to work at an ISP for several years. Back then I wouldn't have used any router that didn't run my custom OpenWRT built with QoS settings, etc.
But times have changed: On my old ADSL line QoS made a huge difference due to congestion (and the large buffer sizes). SSH was nearly unusable while uploading a file. My current Comcast line is so fast that I don't experience any issues due to congestion - so how would I benefit from QoS?
Another difference is that in the past consumer-level hardware was just unreliable: I remember an old Netgear router that just crashed if there were too many concurrent TCP connections, as its NAT table would overflow. I haven't seen those issues in a long time now.
No - I'm not. But my connection works well enough and I don't notice any delays on either SSH or VoIP connections. So why should I invest time/energy into changing something that doesn't affect me?
I'd be interested to know how much the average HN user cares about this. I certainly don't. I'm not even entirely sure how fast my home internet connection is - it's certainly fast enough for me to stream Netflix etc as well as connect to a VPN for working from home. I don't really care about anything else.
(not that my internet connection is always great - it isn't - but that lies with my internet provider, who I have no choice over, so...)
I think there are a lot of smart people on HN, but that doesn't mean they're all interested in all the same things. Tweaking wifi settings just seems like a waste of time to me, and boring to top it off. My interaction with my AP stopped at setting the ssid and passphrase.
Tweaking QoS settings is largely a waste of time nowadays, but only if your router is running an OS new enough to include modern self-tuning QoS algorithms (and preferably a community-maintained project like OpenWRT, because the commercial vendors screw up their deployment of said algorithms).
Even if you aren't going to be hacking on your router much, it still definitely pays to ensure you're using hackable hardware.
Because you get the benefits of those who do hack, simply by installing a recent stable version of OpenWRT. It's no harder than upgrading and configuring the vendor's firmware. If you tie yourself to vendor firmware, you're tying yourself to 5+ year old kernels and all the associated security and performance and stability problems and a much more restricted feature set.
The commercial vendors do an absolutely horrible job of supporting or maintaining their products and they tend to get a lot wrong with the initial software release. The OpenWRT community does a great job of putting out a solid product that works and has sensible defaults, but you can only get the full benefit of their work if you buy hardware that is open to their hacking.
Slightly off topic, but I was surprised to find that my fios provided modem/router/AP gave me a root shell out of the box, and actiontec has the full toolchain to build for it published.
With some uverse subscriptions, you have to use the ISP provided access point (at least as a modem, not necessarily for wireless) because the TV service is through IPTV and the uverse modem is needed do dns for the TV (you also can't use an arbitrary alternative dns server).
In addition to the other answers many of the ISPs provide their hardware on essentially a rental model. The benefit to that is that if you complain loud enough they'll replace it on their dime: the detriment is the same as with any rental though, typically they overcharge you versus what you would pay if you bought it yourself. Your mileage will probably vary, but I've certainly saved money in the long run owning my own equipment, even paying for my own replacements versus storm damage and similar.
Another consideration is that often they will try to use the fact that you don't use their hardware as an excuse to not go further in troubleshooting since they "don't support 3rd party hardware."
It's fun when you get the opposite too and they follow their support scripts regardless of your 3rd party hardware and above average knowledge of the subject:
Support: On your hardware, do x.
Me: Did it already. It reported "Y".
Support: Please do it again, following these scripted steps [what don't match my actual hardware]...
