The analogy between tennis and boxing is often made, including by players, and surely some people like it for this reason like castroneves and maybe Satasonic,
but personally I don't like this dimension of tennis or this comparison at all.
This dimension rather disturbs me.
I mean of course you have to "believe" more than your opponent and it's very important to be careful of your opponent's moments of weakness and be able to take benefit of them, but I don't like the violent connotation of that "I will kill/destroy you" (and that part really exists in tennis : Nadal even used that word once in an interview by lapsus in a very honest way and it made the interviewer laugh but it was just sincere
But I think this association with boxing is made by many spectators.
I'm more attracted by the geometric and "dancing" part.
Of course that partly explains why I'm attracted by Fed whereas some others are attracted by Nadal (see Murray for instance who's in love with both boxing and Nadal)