One can lead a horse to water is equally applicable to educating players.
As you said, attempting to educate players usually results in failure. However, most new players I would say are aware to some extent. They are camping because all they have learned is that going forward will result in them getting deleted from across the map. If players didn't die immediately from this, and could at least see their enemies, camping newbies wouldn't be nearly as much of a problem. In addition to this, it isn't that simple to teach new players how to avoid getting shot by TDs. You can tell them everything they need to know, but there is still a massive jump when it comes to putting that into use in battle. It is a hell of a lot easier for a new player to avoid damage from an enemy they can see than one they cannot (that also has a massive gun that penetrates almost everything). And really, what is the value of it to a new player? Currently TDs are the easiest class to play. Especially with the camo system we have in blitz, you let your team spot the reds and farm easy damage with little risk. That's a whole lot of effort to learn to fight against a class that takes very little skill to play.
And I also don't suggest nerfing TDs to oblivion. TDs could get a compensation for the camo they lose. All the camo loss is for is to force TD drivers to think and to give new players a better chance without gaining the bad habits that they do nowadays.