An extra 6 length from your animation still means the vast majority of two handers will outreach you and won't really do much. This is terrible shielder advice, reach is the one thing you don't have over two-handers so why would you death-sentence yourself by S-Keying and doing exactly what they want you to do...
Right swings on a 1hander give you about 45 bonus reach, 2handers get about 30 reach on sideswings. Most 1handed swords are 100 reach, and 2hand greatswords are 120 reach. So if you use a right swing, you basically are swinging a greatsword yourself. Odds are you have lighter armor and more athletics than a heavy 2hander as well. The stab on a 1hander is about as long as right swings, but are definitely more predictable.
If you are wearing lighter armor/have higher athletics then a 2hander, this lets you dominate a "range game" player. You can simply backpedal so they miss a swing, then immediately close the distance with a right swing. Or if they have their guard down, you wind up a right swing while far away and sprint at them while releasing and they won't know what hit them. 2handers expect to dominate shielders on reach and speed alone very often, so instead of "doing exactly what they want you to do" you are playing one step ahead and turning their expectations against them. Shorter blunt/pierce weapons don't literally outreach greatswords, but you can deceive people and land in easy hits with right swings at safe distances still.
Of course, there is tried and true "facehug, circlestrafe to the right and spam left swings" which will effortlessly cut through bad players but will not work against a good kicker, blocker, or hiltslasher. 1handers can be confusing up close so you can do some feinting if they can handle spam. Stabs on all weapons have seen a decent buff with better activation times and less glances, so if you ever switch to a weapon that can stab feel free to use it at any distance.
Probably the biggest hurdle for a new player against the average 2hand kuyak douchebag is footwork and aggression. Until you get a hang of things, just backpedal if you need space and keep them on the center of your screen at all times. Don't be passive either. 1handers are fast with great animations, and you can get 1-2 hits in for every single hit they get on your shield, sometimes more. Don't let spammers spam your shield, just punish them with a quick sidestep and a good swing and melee will click pretty fast.