Back in my youth, I was heavy into online gaming and building/running public game servers. Going back to the dial up days, where yes some of us learned to tweak COM ports and dial up modems, and knew which models of modems performed better than others. Then came the broadband days...usually not a problem because back in those days most house holds only had 1 or maybe 2 devices connected to your home internet connection. So having to deal with controlling the network and avail bandwidth wasn't an issue for most. I remember those early days, I had co-located some game servers at a small high performance ISP in my state, about 55 miles away from me. I also used them for my DSL at my house. The advantage of that deal, I literally had just 1x hop from my gaming rig..to my game server. It was my router. I had latency of about...oh, 8 maybe 10 ms.

Other people typically around 75-125. I'd been to LAN parties with more lag...LOL. Back then most routers were bland, boring. The first Linksys BEFSR41 models, and Netgears RT312. I always played with different routers to learn them, and just..forever on the quest for "more horsepower!" For a while I even had a pretty expensive Netopia R910.
And then we started seeing routers come out boasting of better performance. There was a company called Nexland, they had this router touting higher performance, it was called the ISB Soho. Of course I had to get that. Was a cool looking thing, transparent case on it.
Fast forward a few years, family time, wife and kids in the home, kids getting old enough to know how to put demanding traffic on the connection. Especially a son into torrenting, a wife eagerly shopping online, and a young daughter watching videos. Here I was trying to game...competing with that traffic. By this time however I was bored with typical "boxed" retail routers, and into building firewalls of various *nix distros. This was back in the Pentium II and III days, I'd take old small form factor PCs and stick a second NIC in 'em and install distros and play with them. PFSense had just come out, like beta version 0.8 or something, and I used this to keep my online playing usable. The big one for me was the penalty box. I'd have the boys PCs IP in there..throttled like crazy! Not really "QoS'..just..give him a straw to sip from and he can't overwhelm your garden hose! PFSense had many other settings to help manage the other traffic and keep mine tip top shape. I used to run it on a IBM Thinkpad...for a while some T20 something model, and later a little X30 or something like that. Perfect platforms for a home *nix router...has a built in KVM and battery backup! I'd just slam in a PCMCIA NIC.
Years later towards the end of my part time gaming career, I enjoyed Tomato firmware on a Cisco e3000 router. It did a good job and keeping online gaming responsive while the rest of the family was busy. Build custom rules for QoS to certain traffic types for your games. Takes a bit of research and experimentation.
I can definitely testify that these "tweaks" worked. I'd have the features turned off...play my game, and have a horrible experience. I'd log in and turn them on, play my game, and it was good. Turn the features off...got lag, turn the features on...no lag. I could repeat that all day all night, 100% reproducible results.
I see the same thing in business networks...large networks, all the time, every day. Good biz grade firewalls have very rich QoS settings to prioritize certain types of traffic. I remember one client, all they could get was dedicated symmetrical T's...no broadband available where their office is. About 20 users, an accounting firm. Early years had a single T-1, more recently doubled...a bonded T...so about 3 megs. Still horrible for about 20 users, right? A while ago I replaced their Adtran router with a linux based UTM firewall..and flipped on the QoS..and the "seat of the pants" usage of the computer felt like the internet speed doubled. I'm talking basic response times for bringing up banking sites, to log into those, and other things. So the QoS prioritized important things for business use (due to a really cool QoS profile feature), services like DNS and HTTPS were prioritized, and services like windows updates, streaming, POP/SMTP/etc..stuff like that is DEprioritized..moves to the back of the line. QoS is like having a good traffic cop at a really busy 4x way intersection...so when an ambulance or fire truck has to get through, the traffic cop holds up other traffic and lets them through!
I never had one of these more current generation routers that focused on gaming, guessing they have a lot of preconfigured rules for common games. Todays homes are certainly filled with tons of devices that hit the internet. Granted most of todays broadband connections are much faster too, but you still can get traffic jams that will overwhelm many routers. ISP provided "all in one gateways" are notoriously horrible for good performance. However simply adding a high performance gaming router behind them (which is what I seem to see >75% of most users do) will not gain performance due to double NAT, a chain is only as strong as its weakest link so the ISP supplied gateway still still bog down doing its NAT. However doing some homework one can bridge model models and have your own router pull the public IP and be in the only NAT.
What I'm not clear about on this unit in the article is how the geoblocking ..well, more specifically...blocking high ping players..helps. The job of allowing, or not allowing, players on a server is...the servers job. Unless they have this feature for people who run game servers. But having people run servers from their homes is less and less popular, with so many games now managed under some umbrella. Maybe it's aimed at console gamers...I'm not sure, not into consoles. I'm certainly aware of low pings and distance of your game server that you play on, generally the closer the server the less distance and less hops your packets have to travel back 'n forth. So maybe it helps filter those out so you only select close servers without having to think about it. back in the old days when I was gaming most people named their Quake and Unreal Tourny (and others) servers with some hint of the geographic area in the name. Or we'd just sort our game server list by ping and select the low ones.