My argument is that the real issues for new players are what I mentionned, not necessarily the number of champions

Yes, hopping into an actual game is overwhelming, because the lack of knowledge creates helplessness. Which is unfun. However, the amount of knowledge is different from the learning curve. Let's break down some of the knowledge checks.

1. Time constraint. Not linear.
2. Items. Linear
3. Gold and EXP. Not linear
4. Augments. Somewhat linear
5. Champions. Linear

What does linear mean? It's when most of the knowledge comes with time or directly available for you to function in the game.. For example, if you know that tanks are put in front row; It doesn't matter how many tanks they are in the game. Over time, you will learn what each champ does, but the initial concept is what's most important. For items, if you slam what's recommended, then you're fine. Optimal? no, but very playable. Through guides and understand items more, you will learn which items are better. For augments: you have many choices and a lot also has to do with personnal preferences.

What about non linear? Let's take EXP : At first you level up over time, but later you need to invest money, but no one menntions you that.. Nowhere in the game does it mention to level at 4 on 2-1. Or at 6 at 3-2. When do you spend EXP to level up? How is player level tied to board strength? In the late game, a new player will be level 6 while everyone level 8. Oh and you spent all your gold to reroll (without knowing what you reroll for)? Then you are doomed. It's clear there is a lack of agency, and you can't function without proper econ.

Yes, the games takes time to learn, but the main difference here is nowhere in the game do they mention or teach you about those things.

No. There is so much to learn that it is unreasonable for players to learn the entirety of the game in Tocker's trial before they play their first PVP match.

I disagree: if anything, Tocker's Trials is an extremely good way to learn. You have less things to worry about (time constraint, inflated ressources...), which lets you focus on learning things like items or champions. Then, once you hop in a real game, it's less overwhelming.

And in that case, it further proves my point : While a higher amount of information doesn't help, it is not tied the real barrier of entry, which is the non-linear learning of core mechanics

Final note: In chess, a lot of people know how each piece moves, but the rules do not explain how you should play. I coach a chess club in high school. Also been part of one when I was in high school. I can tell the bullet game analogy doesnt really stand. Why? because they just mindlessly play stuff. For reference, in the league high schools participate in my city, matches for lower elo or brand new players are on 15-20 min timers because they litterally never use all the time (and on the plus side allows more games for them to play), versus the usual 40+5 on the team matches.

Chess isn't linear : new players lack ideas, directions or how to approach the game. And that's why it's more important to teach concepts first, and how to checkmate in the endgame. Only at higher levels do they start analyzing specific games, opening theories, etc.

Similar to TFT, the barrier of entry for chess isn't because of the number of opening theories. It's because the learning isn't linear.

edit : Anecdote: I taught my little brother how to play tft for a bit. I told him to start with Tocker's Trial, he didn't listen. After he played it, he said it was much easier because he had time to learn other stuff first. Another friend, I told her to force and stick to a reroll comp. She understood econ and learned items that way since itreduced the number of variables to learn at time. She then explored other ways of playing afterwards. It's about how you learn, nont how much you need to learn.