Training with computer during analysis is not strong enough.

For my experience, if u push this "target" button "computer training" during analyse of position, this "training" stockfish edition dont tries to punish u hard sometimes, as stockfish always do. I mean, especially in endgame, robot dont usually tries to check your technique of realisation extra pawn or smth, also it often not too hard to force exchanges to simplify position. I think this robot dont go for 1st line. So for lichess i think its nice idea to add levels of training too. Like, if u choose "hard" in settings robot will always play for 1st line, tries to never exchange and always check all your theory knowelege.

There are no settings to adjust the level of training already ?

It think the "target" button during analysis allows you to focus on a specific move or sequence, it does not necessarily mean that the program will play less aggressively or try to simplify the position. In fact, the purpose of the "target" button is to help you find the best move in a given position, which may involve making aggressive or complex moves.

However, it is worth noting that playing against a computer opponent is not the same as playing against a human opponent, and improving your chess skills requires playing against other humans as well.