Tonsils and appendixes are not removed whimsically or voluntarily, ever. Back around the 1950s or 60s they'd sometimes whip tonsils out on a whim, just to save potential trouble from tonsilitis down the line, but then somebody discovered tonsils are actually there for a good reason, just like every other organ, and the orthodoxy quickly changed to leaving them in place unless removal was absolutely necessary. They are a front-line defense against disease, btw, their inflammation is a result of them attacking invading germs.
The appendix is only taken out when it is burst, about to burst, or looks like it is likely to burst. It's mostly superfluous, but all surgery carries a certain risk, particularly cutting out a bag full of bacteria like an appendix and having it leak everywhere.
There are no ordinary, medically-accepted occasions of voluntary removing anything. The only people who do that are the weird body-modder crowd, who blur into the BDSM crowd if you were drawing a Venn diagram. Their "surgery" is generally illegal and carried out in tattoo shops and the like. Very occasionally you might get an actual dentist performing such surgery. But, yes, this does include castration, but it's absolutely non-medical as well as criminal.
There's the consideration, too, that human behaviour is a complex thing born of character and life experience, as well as to a certain extent, one's genome. Whipping off a small gland does not produce direct and straightforward changes in behaviour. One instance would be the fact that oestrogen was once used as "chemical castration", that is, the drug-based suppression of the male sex drive, and also impotence. Despite the name, no actual damage occurs to the testes. It was long-accepted that oestrogen would render a man impotent and harmless. And then autogynephiles turned up, for whom all of that is their actual fetish. Taking female hormones is itself a turnon, and living their fantasy increases their sex drive. Such people are also proof that a simple bit of hormone engineering can't change behaviour, they act very much like a man's idea of what a "woman" is, often in a pornographic or fetish sense.
I'm sure it doesn't need saying, but cutting your nuts off isn't going to end well. You'd be as likely to still have a sex drive, but now have no way of releasing it. You might even find that with a major source of anxiety gone, and free of desperation for sex, you relate to women much better, a disastrous result of castrating yourself!