I see many great post and feedback in this thread.
I will take this time to explain a few things
Major reasons why Legion is counter productive for twinks.
For the 20 bracket, the thing that made it so unique was the feats/perks that you had to earn.
In cata when alot of the F2P community started things were basically its own endgame.
When i started F2P like many others the only thing we had was quest and dungeon gear.
Players had to do tons of pve just to get the basic gear sets in order to be effective in bgs.
Learning Abilities and Player Improvement:
In order to gain better gear players needed to actually win Battlegrounds. As many of us here remember a little thing called Call to Arms.
Gaining Honor and Justice points was a real grind. You really had to dedicate time and really had to win in order to fully gear characters out.
By there being a need to win in order to receive a reward that would better your character, players were more willing to work as a team. The players that already had a good grasp on the game would always be yelling whispering and telling newer players what they should be doing. After ignoring the directions of the pro players , newer players began to see they would lose these important battlegrounds. The new players would eventually try some of the advice and see it worked. Now the newer players are interesting in knowing more strats and ways to win. New players would see Lucky Fishing Hat and Arena Grand Master and be blinded. They wanted to be geared just like those Paladins and 1600 HP survival Hunters.
Communities:
In F2P we had many communities some large and some smaller. As i mentioned above there was a need to work as a team in order to gain gear faster by winning bgs. This need of teamwork made communities like Aerie Peak Vashj BWL Aggramar and Twisting Neither go to places for people. On these realms there were always groups of 5 and 10 getting ready to bg all day. This way you did not have to worry about a 2-2 game being lost because 1 or 2 newer players made mistakes.
Overtime you would get to know the people you see often because the way battlegroups worked. Even people who did not like you or you did not like would work with you and know what to expect of you. on Sundays on Aggramar there would be 70 + people online. You had a group of people gearing new Characters so new players would join groups with them and rn 5 man dungeons all day. There were the people who had full dungeon gear and wanted heirlooms or tabards just to show off plus tittles, whom be running 5-10 man bgs. This leads into one of my favorite things about Cata and Mop.
Rivalries :
Due to the large number on realms running 5 and 10 man premades rivalries began to form. The slick thing about gear taking longer to obtain was this normally made me dedicated to one realm and one faction for a long amount of time. This would cause huge clashes during Call to Arms. People were very serious during these games as well.
On EU horde was known for people such as Rusty Clinic Interlope Goblinhood showing up with their notorious 5 man premades and sometimes more. Then to make matters worse for alliance Aggramar would have Dasha Reham Interuptz Lolipop Junoo Mol Beastasky Maratain and the rest of the Aggramar crew merging 5 mans with the 24s or sometimes a full 10 man aggramar group. This is where things get interesting. Alliance was made up of smaller groups of people on multiple realms. Twisting Neither, Magtheridon Mazrigos and ofc Ravencrest stepped in. Alliance would do well with me Cripzblood Flipzmytoast Moonseeker Canashot Mysterious Poledancer Trickynick and others but sometimes when the 24s got involved it would be a close game but the 24s would edge the game out.
This is where GSC came into play. Yes thats right GSC formed in order to counter the 24s on Horde EU, 4 years b4 appearing in the twink cup. Now you had not only 20s fighting together against their faction counterpart but even the 24s were joining up against each other. Games were really crazy and intense. Many times games would go down to the last cap. People made names for themselves by actually impacting the games not by posting on the forums back then. There was no arguing about who did this and who didn't because everyone could see ingame.
Arenas :
Heirloom tab along with cross realmzones took the gearing up/reward factor, community growth factor away.
With cross realm zones people no longer needed to all be on the same realm and with the loom tab they could play what ever toon they wanted on any realm. The bnet addtion made things where u could just group with people u know from separate realms and skip over the entire F2P Chat Addon process of LF BGs etc.
Arenas were a thing where once you had so much battleground practice and geared your toon, it was time to step up to the plate. Arenas are smaller groups of people so your mistakes and individual play is extremely noticeable even if you are considered average. I remember transferring over from EU to US for Arenas. Many people including myself had saw Wizkidone videos and saw all the buzz Aerie Peak was getting at the time. I had to see if this was really a level of play higher than what i previous experienced. It was a great decision to see for my self. The games were decided so much faster and by such slight windows of opportunity plus errors. I met the top dogs on Aerie Peak such as Wizkidone Flynn Fael Oldspike Hydox Oldspike Cer Hue Krews Veinte and many many more. Hydox and Fael immediately told me that just because i played hunter for 2 years prior and wrecked people in bgs doesnt mean i have enough skill for arenas. Overtime i got over playing 1 op class and started learning more about all of the classes.
Through all of these experiences i was able to Create the F2P Championship. I was able to draw new players into our community. I had went through all of this as a new player myself and i knew the mindset of the people who were just arriving. Legion hands too much to players off the get go. This is why i believe Twinking overall has not become better in Legion.